diff --git a/src/LogInit.cxx b/src/LogInit.cxx
index d240f71e2..98a8810bd 100644
--- a/src/LogInit.cxx
+++ b/src/LogInit.cxx
@@ -234,7 +234,7 @@ cycle_log_files() noexcept
 	if (out_path.IsNull())
 		return 0;
 
-	FormatDebug(log_domain, "Cycling log files");
+	LogDebug(log_domain, "Cycling log files");
 	close_log_files();
 
 	fd = open_log_file();
diff --git a/src/client/Expire.cxx b/src/client/Expire.cxx
index 961bf03e0..f6bc5951c 100644
--- a/src/client/Expire.cxx
+++ b/src/client/Expire.cxx
@@ -44,7 +44,7 @@ Client::OnTimeout() noexcept
 		assert(!idle_waiting);
 		assert(!background_command);
 
-		FormatDebug(client_domain, "[%u] timeout", num);
+		FmtDebug(client_domain, "[{}] timeout", num);
 	}
 
 	Close();
diff --git a/src/db/update/Service.cxx b/src/db/update/Service.cxx
index b399cf6be..fc16a15cd 100644
--- a/src/db/update/Service.cxx
+++ b/src/db/update/Service.cxx
@@ -113,8 +113,7 @@ UpdateService::Task() noexcept
 	SetThreadName("update");
 
 	if (!next.path_utf8.empty())
-		FormatDebug(update_domain, "starting: %s",
-			    next.path_utf8.c_str());
+		FmtDebug(update_domain, "starting: {}", next.path_utf8);
 	else
 		LogDebug(update_domain, "starting");
 
@@ -133,8 +132,7 @@ UpdateService::Task() noexcept
 	}
 
 	if (!next.path_utf8.empty())
-		FormatDebug(update_domain, "finished: %s",
-			    next.path_utf8.c_str());
+		FmtDebug(update_domain, "finished: {}", next.path_utf8);
 	else
 		LogDebug(update_domain, "finished");
 
@@ -155,8 +153,8 @@ UpdateService::StartThread(UpdateQueueItem &&i)
 
 	update_thread.Start();
 
-	FormatDebug(update_domain,
-		    "spawned thread for update job id %i", next.id);
+	FmtDebug(update_domain,
+		 "spawned thread for update job id {}", next.id);
 }
 
 unsigned
diff --git a/src/decoder/Bridge.cxx b/src/decoder/Bridge.cxx
index 79ef2c4f7..ae034bb4d 100644
--- a/src/decoder/Bridge.cxx
+++ b/src/decoder/Bridge.cxx
@@ -21,6 +21,7 @@
 #include "DecoderAPI.hxx"
 #include "Domain.hxx"
 #include "Control.hxx"
+#include "lib/fmt/AudioFormatFormatter.hxx"
 #include "song/DetachedSong.hxx"
 #include "pcm/Convert.hxx"
 #include "MusicPipe.hxx"
@@ -268,9 +269,9 @@ DecoderBridge::Ready(const AudioFormat audio_format,
 	assert(decoder_tag == nullptr);
 	assert(!seeking);
 
-	FormatDebug(decoder_domain, "audio_format=%s, seekable=%s",
-		    ToString(audio_format).c_str(),
-		    seekable ? "true" : "false");
+	FmtDebug(decoder_domain, "audio_format={}, seekable={}",
+		 audio_format,
+		 seekable);
 
 	{
 		const std::lock_guard<Mutex> protect(dc.mutex);
@@ -278,8 +279,8 @@ DecoderBridge::Ready(const AudioFormat audio_format,
 	}
 
 	if (dc.in_audio_format != dc.out_audio_format) {
-		FormatDebug(decoder_domain, "converting to %s",
-			    ToString(dc.out_audio_format).c_str());
+		FmtDebug(decoder_domain, "converting to %s",
+			 dc.out_audio_format);
 
 		try {
 			convert = std::make_unique<PcmConvert>(dc.in_audio_format,
diff --git a/src/decoder/Thread.cxx b/src/decoder/Thread.cxx
index 9ea46560f..6e4793747 100644
--- a/src/decoder/Thread.cxx
+++ b/src/decoder/Thread.cxx
@@ -61,7 +61,7 @@ DecoderUriDecode(const DecoderPlugin &plugin,
 	assert(uri != nullptr);
 	assert(bridge.dc.state == DecoderState::START);
 
-	FormatDebug(decoder_thread_domain, "probing plugin %s", plugin.name);
+	FmtDebug(decoder_thread_domain, "probing plugin {}", plugin.name);
 
 	if (bridge.dc.command == DecoderCommand::STOP)
 		throw StopDecoder();
@@ -99,7 +99,7 @@ decoder_stream_decode(const DecoderPlugin &plugin,
 	assert(input_stream.IsReady());
 	assert(bridge.dc.state == DecoderState::START);
 
-	FormatDebug(decoder_thread_domain, "probing plugin %s", plugin.name);
+	FmtDebug(decoder_thread_domain, "probing plugin {}", plugin.name);
 
 	if (bridge.dc.command == DecoderCommand::STOP)
 		throw StopDecoder();
@@ -142,7 +142,7 @@ decoder_file_decode(const DecoderPlugin &plugin,
 	assert(path.IsAbsolute());
 	assert(bridge.dc.state == DecoderState::START);
 
-	FormatDebug(decoder_thread_domain, "probing plugin %s", plugin.name);
+	FmtDebug(decoder_thread_domain, "probing plugin {}", plugin.name);
 
 	if (bridge.dc.command == DecoderCommand::STOP)
 		throw StopDecoder();
diff --git a/src/decoder/plugins/AdPlugDecoderPlugin.cxx b/src/decoder/plugins/AdPlugDecoderPlugin.cxx
index fcd2c84dc..a494847d0 100644
--- a/src/decoder/plugins/AdPlugDecoderPlugin.cxx
+++ b/src/decoder/plugins/AdPlugDecoderPlugin.cxx
@@ -38,8 +38,8 @@ static unsigned sample_rate;
 static bool
 adplug_init(const ConfigBlock &block)
 {
-	FormatDebug(adplug_domain, "adplug %s",
-		    CAdPlug::get_version().c_str());
+	FmtDebug(adplug_domain, "adplug {}",
+		 CAdPlug::get_version());
 
 	sample_rate = block.GetPositiveValue("sample_rate", 48000U);
 	CheckSampleRate(sample_rate);
diff --git a/src/decoder/plugins/AudiofileDecoderPlugin.cxx b/src/decoder/plugins/AudiofileDecoderPlugin.cxx
index 437bddedd..d6457f7eb 100644
--- a/src/decoder/plugins/AudiofileDecoderPlugin.cxx
+++ b/src/decoder/plugins/AudiofileDecoderPlugin.cxx
@@ -168,8 +168,8 @@ audiofile_setup_sample_format(AFfilehandle af_fp) noexcept
 
 	afGetSampleFormat(af_fp, AF_DEFAULT_TRACK, &fs, &bits);
 	if (!audio_valid_sample_format(audiofile_bits_to_sample_format(bits))) {
-		FormatDebug(audiofile_domain,
-			    "input file has %d bit samples, converting to 16",
+		FmtDebug(audiofile_domain,
+			    "input file has {} bit samples, converting to 16",
 			    bits);
 		bits = 16;
 	}
diff --git a/src/decoder/plugins/FlacDecoderPlugin.cxx b/src/decoder/plugins/FlacDecoderPlugin.cxx
index 948783f6d..80d124127 100644
--- a/src/decoder/plugins/FlacDecoderPlugin.cxx
+++ b/src/decoder/plugins/FlacDecoderPlugin.cxx
@@ -73,9 +73,9 @@ flac_scan_file(Path path_fs, TagHandler &handler)
 {
 	FlacMetadataChain chain;
 	if (!chain.Read(NarrowPath(path_fs))) {
-		FormatDebug(flac_domain,
-			    "Failed to read FLAC tags: %s",
-			    chain.GetStatusString());
+		FmtDebug(flac_domain,
+			 "Failed to read FLAC tags: {}",
+			 chain.GetStatusString());
 		return false;
 	}
 
@@ -88,9 +88,9 @@ flac_scan_stream(InputStream &is, TagHandler &handler)
 {
 	FlacMetadataChain chain;
 	if (!chain.Read(is)) {
-		FormatDebug(flac_domain,
-			    "Failed to read FLAC tags: %s",
-			    chain.GetStatusString());
+		FmtDebug(flac_domain,
+			 "Failed to read FLAC tags: {}",
+			 chain.GetStatusString());
 		return false;
 	}
 
@@ -317,9 +317,9 @@ oggflac_scan_file(Path path_fs, TagHandler &handler)
 {
 	FlacMetadataChain chain;
 	if (!chain.ReadOgg(NarrowPath(path_fs))) {
-		FormatDebug(flac_domain,
-			    "Failed to read OggFLAC tags: %s",
-			    chain.GetStatusString());
+		FmtDebug(flac_domain,
+			 "Failed to read OggFLAC tags: {}",
+			 chain.GetStatusString());
 		return false;
 	}
 
@@ -332,9 +332,9 @@ oggflac_scan_stream(InputStream &is, TagHandler &handler)
 {
 	FlacMetadataChain chain;
 	if (!chain.ReadOgg(is)) {
-		FormatDebug(flac_domain,
-			    "Failed to read OggFLAC tags: %s",
-			    chain.GetStatusString());
+		FmtDebug(flac_domain,
+			 "Failed to read OggFLAC tags: {}",
+			 chain.GetStatusString());
 		return false;
 	}
 
diff --git a/src/decoder/plugins/GmeDecoderPlugin.cxx b/src/decoder/plugins/GmeDecoderPlugin.cxx
index f279d95b0..66d35a5fa 100644
--- a/src/decoder/plugins/GmeDecoderPlugin.cxx
+++ b/src/decoder/plugins/GmeDecoderPlugin.cxx
@@ -160,8 +160,8 @@ gme_file_decode(DecoderClient &client, Path path_fs)
 
 	AtScopeExit(emu) { gme_delete(emu); };
 
-	FormatDebug(gme_domain, "emulator type '%s'\n",
-		    gme_type_system(gme_type(emu)));
+	FmtDebug(gme_domain, "emulator type '{}'",
+		 gme_type_system(gme_type(emu)));
 
 #if GME_VERSION >= 0x000600
 	if (gme_accuracy >= 0)
diff --git a/src/decoder/plugins/MadDecoderPlugin.cxx b/src/decoder/plugins/MadDecoderPlugin.cxx
index 557efdfd4..e1a2f0cf6 100644
--- a/src/decoder/plugins/MadDecoderPlugin.cxx
+++ b/src/decoder/plugins/MadDecoderPlugin.cxx
@@ -382,9 +382,9 @@ RecoverFrameError(const struct mad_stream &stream) noexcept
 	if (MAD_RECOVERABLE(stream.error))
 		return MadDecoderAction::SKIP;
 
-	FormatWarning(mad_domain,
-		      "unrecoverable frame level error: %s",
-		      mad_stream_errorstr(&stream));
+	FmtWarning(mad_domain,
+		   "unrecoverable frame level error: {}",
+		   mad_stream_errorstr(&stream));
 	return MadDecoderAction::BREAK;
 }
 
@@ -571,8 +571,8 @@ parse_lame(struct lame *lame, struct mad_bitptr *ptr, int *bitlen) noexcept
 	           &lame->version.major, &lame->version.minor) != 2)
 		return false;
 
-	FormatDebug(mad_domain, "detected LAME version %i.%i (\"%s\")",
-		    lame->version.major, lame->version.minor, lame->encoder);
+	FmtDebug(mad_domain, "detected LAME version {}.{} (\"{}\")",
+		 lame->version.major, lame->version.minor, lame->encoder);
 
 	/* The reference volume was changed from the 83dB used in the
 	 * ReplayGain spec to 89dB in lame 3.95.1.  Bump the gain for older
@@ -589,7 +589,7 @@ parse_lame(struct lame *lame, struct mad_bitptr *ptr, int *bitlen) noexcept
 	mad_bit_skip(ptr, 16);
 
 	lame->peak = MAD_F(mad_bit_read(ptr, 32) << 5); /* peak */
-	FormatDebug(mad_domain, "LAME peak found: %f", double(lame->peak));
+	FmtDebug(mad_domain, "LAME peak found: {}", lame->peak);
 
 	lame->track_gain = 0;
 	unsigned name = mad_bit_read(ptr, 3); /* gain name */
@@ -598,8 +598,8 @@ parse_lame(struct lame *lame, struct mad_bitptr *ptr, int *bitlen) noexcept
 	int gain = mad_bit_read(ptr, 9); /* gain*10 */
 	if (gain && name == 1 && orig != 0) {
 		lame->track_gain = ((sign ? -gain : gain) / 10.0f) + adj;
-		FormatDebug(mad_domain, "LAME track gain found: %f",
-			    double(lame->track_gain));
+		FmtDebug(mad_domain, "LAME track gain found: {}",
+			 lame->track_gain);
 	}
 
 	/* tmz reports that this isn't currently written by any version of lame
@@ -614,8 +614,8 @@ parse_lame(struct lame *lame, struct mad_bitptr *ptr, int *bitlen) noexcept
 	gain = mad_bit_read(ptr, 9); /* gain*10 */
 	if (gain && name == 2 && orig != 0) {
 		lame->album_gain = ((sign ? -gain : gain) / 10.0) + adj;
-		FormatDebug(mad_domain, "LAME album gain found: %f",
-			    double(lame->track_gain));
+		FmtDebug(mad_domain, "LAME album gain found: {}",
+			 lame->track_gain);
 	}
 #else
 	mad_bit_skip(ptr, 16);
@@ -626,8 +626,8 @@ parse_lame(struct lame *lame, struct mad_bitptr *ptr, int *bitlen) noexcept
 	lame->encoder_delay = mad_bit_read(ptr, 12);
 	lame->encoder_padding = mad_bit_read(ptr, 12);
 
-	FormatDebug(mad_domain, "encoder delay is %i, encoder padding is %i",
-		    lame->encoder_delay, lame->encoder_padding);
+	FmtDebug(mad_domain, "encoder delay is {}, encoder padding is {}",
+		 lame->encoder_delay, lame->encoder_padding);
 
 	mad_bit_skip(ptr, 80);
 
@@ -763,9 +763,9 @@ MadDecoder::DecodeFirstFrame(Tag *tag) noexcept
 		return false;
 
 	if (max_frames > 8 * 1024 * 1024) {
-		FormatWarning(mad_domain,
-			      "mp3 file header indicates too many frames: %zu",
-			      max_frames);
+		FmtWarning(mad_domain,
+			   "mp3 file header indicates too many frames: {}",
+			   max_frames);
 		return false;
 	}
 
diff --git a/src/decoder/plugins/PcmDecoderPlugin.cxx b/src/decoder/plugins/PcmDecoderPlugin.cxx
index ccdd6cd36..6fae29a1c 100644
--- a/src/decoder/plugins/PcmDecoderPlugin.cxx
+++ b/src/decoder/plugins/PcmDecoderPlugin.cxx
@@ -101,9 +101,9 @@ pcm_stream_decode(DecoderClient &client, InputStream &is)
 			char *endptr;
 			unsigned value = ParseUnsigned(s, &endptr);
 			if (endptr == s || *endptr != 0) {
-				FormatWarning(pcm_decoder_domain,
-					      "Failed to parse sample rate: %s",
-					      s);
+				FmtWarning(pcm_decoder_domain,
+					   "Failed to parse sample rate: {}",
+					   s);
 				return;
 			}
 
@@ -123,9 +123,9 @@ pcm_stream_decode(DecoderClient &client, InputStream &is)
 			char *endptr;
 			unsigned value = ParseUnsigned(s, &endptr);
 			if (endptr == s || *endptr != 0) {
-				FormatWarning(pcm_decoder_domain,
-					      "Failed to parse sample rate: %s",
-					      s);
+				FmtWarning(pcm_decoder_domain,
+					   "Failed to parse sample rate: {}",
+					   s);
 				return;
 			}
 
@@ -146,9 +146,9 @@ pcm_stream_decode(DecoderClient &client, InputStream &is)
 				const char *s = i->second.c_str();
 				audio_format = ParseAudioFormat(s, false);
 				if (!audio_format.IsFullyDefined()) {
-					FormatWarning(pcm_decoder_domain,
-							  "Invalid audio format specification: %s",
-							  mime);
+					FmtWarning(pcm_decoder_domain,
+						   "Invalid audio format specification: {}",
+						   mime);
 					return;
 				}
 			}
@@ -157,9 +157,9 @@ pcm_stream_decode(DecoderClient &client, InputStream &is)
 	}
 
 	if (audio_format.sample_rate == 0) {
-		FormatWarning(pcm_decoder_domain,
-			      "Missing 'rate' parameter: %s",
-			      mime);
+		FmtWarning(pcm_decoder_domain,
+			   "Missing 'rate' parameter: {}",
+			   mime);
 		return;
 	}
 
diff --git a/src/decoder/plugins/SidplayDecoderPlugin.cxx b/src/decoder/plugins/SidplayDecoderPlugin.cxx
index ba13e6ff4..3dc2fb156 100644
--- a/src/decoder/plugins/SidplayDecoderPlugin.cxx
+++ b/src/decoder/plugins/SidplayDecoderPlugin.cxx
@@ -254,8 +254,7 @@ sidplay_file_decode(DecoderClient &client, Path path_fs)
 #else
 		const char *error = tune.getInfo().statusString;
 #endif
-		FormatWarning(sidplay_domain, "failed to load file: %s",
-			      error);
+		FmtWarning(sidplay_domain, "failed to load file: {}", error);
 		return;
 	}
 
@@ -283,8 +282,8 @@ sidplay_file_decode(DecoderClient &client, Path path_fs)
 	bool error = player.load(&tune) < 0;
 #endif
 	if (error) {
-		FormatWarning(sidplay_domain,
-			      "sidplay2.load() failed: %s", player.error());
+		FmtWarning(sidplay_domain,
+			   "sidplay2.load() failed: {}", player.error());
 		return;
 	}
 
@@ -293,25 +292,25 @@ sidplay_file_decode(DecoderClient &client, Path path_fs)
 #ifdef HAVE_SIDPLAYFP
 	ReSIDfpBuilder builder("ReSID");
 	if (!builder.getStatus()) {
-		FormatWarning(sidplay_domain,
-			      "failed to initialize ReSIDfpBuilder: %s",
-			      builder.error());
+		FmtWarning(sidplay_domain,
+			   "failed to initialize ReSIDfpBuilder: {}",
+			   builder.error());
 		return;
 	}
 
 	builder.create(player.info().maxsids());
 	if (!builder.getStatus()) {
-		FormatWarning(sidplay_domain,
-			      "ReSIDfpBuilder.create() failed: %s",
-			      builder.error());
+		FmtWarning(sidplay_domain,
+			   "ReSIDfpBuilder.create() failed: {}",
+			   builder.error());
 		return;
 	}
 #else
 	ReSIDBuilder builder("ReSID");
 	builder.create(player.info().maxsids);
 	if (!builder) {
-		FormatWarning(sidplay_domain, "ReSIDBuilder.create() failed: %s",
-			      builder.error());
+		FmtWarning(sidplay_domain, "ReSIDBuilder.create() failed: {}",
+			   builder.error());
 		return;
 	}
 #endif
@@ -319,15 +318,15 @@ sidplay_file_decode(DecoderClient &client, Path path_fs)
 	builder.filter(sidplay_global->filter_setting);
 #ifdef HAVE_SIDPLAYFP
 	if (!builder.getStatus()) {
-		FormatWarning(sidplay_domain,
-			      "ReSIDfpBuilder.filter() failed: %s",
-			      builder.error());
+		FmtWarning(sidplay_domain,
+			   "ReSIDfpBuilder.filter() failed: {}",
+			   builder.error());
 		return;
 	}
 #else
 	if (!builder) {
-		FormatWarning(sidplay_domain, "ReSIDBuilder.filter() failed: %s",
-			      builder.error());
+		FmtWarning(sidplay_domain, "ReSIDBuilder.filter() failed: {}",
+			   builder.error());
 		return;
 	}
 #endif
@@ -388,8 +387,8 @@ sidplay_file_decode(DecoderClient &client, Path path_fs)
 	error = player.config(config) < 0;
 #endif
 	if (error) {
-		FormatWarning(sidplay_domain,
-			      "sidplay2.config() failed: %s", player.error());
+		FmtWarning(sidplay_domain,
+			   "sidplay2.config() failed: {}", player.error());
 		return;
 	}
 
diff --git a/src/decoder/plugins/SndfileDecoderPlugin.cxx b/src/decoder/plugins/SndfileDecoderPlugin.cxx
index ae814d71c..1dedf8bd9 100644
--- a/src/decoder/plugins/SndfileDecoderPlugin.cxx
+++ b/src/decoder/plugins/SndfileDecoderPlugin.cxx
@@ -203,8 +203,8 @@ sndfile_stream_decode(DecoderClient &client, InputStream &is)
 	SNDFILE *const sf = sf_open_virtual(const_cast<SF_VIRTUAL_IO *>(&vio),
 					    SFM_READ, &info, &sis);
 	if (sf == nullptr) {
-		FormatWarning(sndfile_domain, "sf_open_virtual() failed: %s",
-			      sf_strerror(nullptr));
+		FmtWarning(sndfile_domain, "sf_open_virtual() failed: {}",
+			   sf_strerror(nullptr));
 		return;
 	}
 
@@ -281,8 +281,8 @@ sndfile_scan_stream(InputStream &is, TagHandler &handler)
 	AtScopeExit(sf) { sf_close(sf); };
 
 	if (!audio_valid_sample_rate(info.samplerate)) {
-		FormatWarning(sndfile_domain,
-			      "Invalid sample rate in %s", is.GetURI());
+		FmtWarning(sndfile_domain,
+			   "Invalid sample rate in {}", is.GetURI());
 		return false;
 	}
 
diff --git a/src/encoder/plugins/TwolameEncoderPlugin.cxx b/src/encoder/plugins/TwolameEncoderPlugin.cxx
index c8e43de33..bd24c041e 100644
--- a/src/encoder/plugins/TwolameEncoderPlugin.cxx
+++ b/src/encoder/plugins/TwolameEncoderPlugin.cxx
@@ -124,8 +124,8 @@ PreparedTwolameEncoder::PreparedTwolameEncoder(const ConfigBlock &block)
 static PreparedEncoder *
 twolame_encoder_init(const ConfigBlock &block)
 {
-	FormatDebug(twolame_encoder_domain,
-		    "libtwolame version %s", get_twolame_version());
+	FmtDebug(twolame_encoder_domain,
+		 "libtwolame version {}", get_twolame_version());
 
 	return new PreparedTwolameEncoder(block);
 }
diff --git a/src/encoder/plugins/meson.build b/src/encoder/plugins/meson.build
index 02362411c..991a1e2cc 100644
--- a/src/encoder/plugins/meson.build
+++ b/src/encoder/plugins/meson.build
@@ -53,6 +53,7 @@ encoder_plugins = static_library(
     liblame_dep,
     libtwolame_dep,
     libshine_dep,
+    log_dep,
   ],
 )
 
diff --git a/src/filter/plugins/ReplayGainFilterPlugin.cxx b/src/filter/plugins/ReplayGainFilterPlugin.cxx
index a776aa0ee..c867640f9 100644
--- a/src/filter/plugins/ReplayGainFilterPlugin.cxx
+++ b/src/filter/plugins/ReplayGainFilterPlugin.cxx
@@ -94,9 +94,9 @@ public:
 			/* no change */
 			return;
 
-		FormatDebug(replay_gain_domain,
-			    "replay gain mode has changed %s->%s\n",
-			    ToString(mode), ToString(_mode));
+		FmtDebug(replay_gain_domain,
+			 "replay gain mode has changed {}->{}",
+			 ToString(mode), ToString(_mode));
 
 		mode = _mode;
 		Update();
@@ -155,8 +155,7 @@ ReplayGainFilter::Update()
 	if (mode != ReplayGainMode::OFF) {
 		const auto &tuple = info.Get(mode);
 		float scale = tuple.CalculateScale(config);
-		FormatDebug(replay_gain_domain,
-			    "scale=%f\n", (double)scale);
+		FmtDebug(replay_gain_domain, "scale={}\n", scale);
 
 		volume = pcm_float_to_volume(scale);
 	}
diff --git a/src/filter/plugins/meson.build b/src/filter/plugins/meson.build
index b0dfb3708..187dcfcc2 100644
--- a/src/filter/plugins/meson.build
+++ b/src/filter/plugins/meson.build
@@ -26,6 +26,7 @@ filter_plugins = static_library(
   include_directories: inc,
   dependencies: [
     filter_plugins_deps,
+    log_dep,
   ],
 )
 
diff --git a/src/input/plugins/AlsaInputPlugin.cxx b/src/input/plugins/AlsaInputPlugin.cxx
index 2c49d0d6e..73a145208 100644
--- a/src/input/plugins/AlsaInputPlugin.cxx
+++ b/src/input/plugins/AlsaInputPlugin.cxx
@@ -270,15 +270,15 @@ AlsaInputStream::Recover(int err)
 {
 	switch(err) {
 	case -EPIPE:
-		FormatDebug(alsa_input_domain,
-			    "Overrun on ALSA capture device \"%s\"",
-			    device.c_str());
+		FmtDebug(alsa_input_domain,
+			 "Overrun on ALSA capture device \"{}\"",
+			 device);
 		break;
 
 	case -ESTRPIPE:
-		FormatDebug(alsa_input_domain,
-			    "ALSA capture device \"%s\" was suspended",
-			    device.c_str());
+		FmtDebug(alsa_input_domain,
+			 "ALSA capture device \"{}\" was suspended",
+			 device);
 		break;
 	}
 
@@ -361,9 +361,9 @@ AlsaInputStream::ConfigureCapture(AudioFormat audio_format)
 	unsigned buffer_time_min, buffer_time_max;
 	snd_pcm_hw_params_get_buffer_time_min(hw_params, &buffer_time_min, nullptr);
 	snd_pcm_hw_params_get_buffer_time_max(hw_params, &buffer_time_max, nullptr);
-	FormatDebug(alsa_input_domain, "buffer: size=%u..%u time=%u..%u",
-		    (unsigned)buffer_size_min, (unsigned)buffer_size_max,
-		    buffer_time_min, buffer_time_max);
+	FmtDebug(alsa_input_domain, "buffer: size={}..{} time={}..{}",
+		 buffer_size_min, buffer_size_max,
+		 buffer_time_min, buffer_time_max);
 
 	snd_pcm_uframes_t period_size_min, period_size_max;
 	snd_pcm_hw_params_get_period_size_min(hw_params, &period_size_min, nullptr);
@@ -371,9 +371,9 @@ AlsaInputStream::ConfigureCapture(AudioFormat audio_format)
 	unsigned period_time_min, period_time_max;
 	snd_pcm_hw_params_get_period_time_min(hw_params, &period_time_min, nullptr);
 	snd_pcm_hw_params_get_period_time_max(hw_params, &period_time_max, nullptr);
-	FormatDebug(alsa_input_domain, "period: size=%u..%u time=%u..%u",
-		    (unsigned)period_size_min, (unsigned)period_size_max,
-		    period_time_min, period_time_max);
+	FmtDebug(alsa_input_domain, "period: size={}..{} time={}..{}",
+		 period_size_min, period_size_max,
+		 period_time_min, period_time_max);
 
 	/* choose the maximum possible buffer_size ... */
 	snd_pcm_hw_params_set_buffer_size(capture_handle, hw_params,
@@ -409,8 +409,8 @@ AlsaInputStream::ConfigureCapture(AudioFormat audio_format)
 		throw FormatRuntimeError("snd_pcm_hw_params_get_period_size() failed: %s",
 					 snd_strerror(-err));
 
-	FormatDebug(alsa_input_domain, "buffer_size=%u period_size=%u",
-		    (unsigned)alsa_buffer_size, (unsigned)alsa_period_size);
+	FmtDebug(alsa_input_domain, "buffer_size={} period_size={}",
+		 alsa_buffer_size, alsa_period_size);
 
 	snd_pcm_sw_params_t *sw_params;
 	snd_pcm_sw_params_alloca(&sw_params);
diff --git a/src/input/plugins/CurlInputPlugin.cxx b/src/input/plugins/CurlInputPlugin.cxx
index 95e3fb9dd..270c564c8 100644
--- a/src/input/plugins/CurlInputPlugin.cxx
+++ b/src/input/plugins/CurlInputPlugin.cxx
@@ -281,10 +281,7 @@ CurlInputStream::OnHeaders(unsigned status,
 
 		if (i != headers.end()) {
 			size_t icy_metaint = ParseUint64(i->second.c_str());
-#ifndef _WIN32
-			/* Windows doesn't know "%z" */
-			FormatDebug(curl_domain, "icy-metaint=%zu", icy_metaint);
-#endif
+			FmtDebug(curl_domain, "icy-metaint={}", icy_metaint);
 
 			if (icy_metaint > 0) {
 				icy->Start(icy_metaint);
@@ -358,10 +355,10 @@ input_curl_init(EventLoop &event_loop, const ConfigBlock &block)
 
 	const auto version_info = curl_version_info(CURLVERSION_FIRST);
 	if (version_info != nullptr) {
-		FormatDebug(curl_domain, "version %s", version_info->version);
+		FmtDebug(curl_domain, "version {}", version_info->version);
 		if (version_info->features & CURL_VERSION_SSL)
-			FormatDebug(curl_domain, "with %s",
-				    version_info->ssl_version);
+			FmtDebug(curl_domain, "with {}",
+				 version_info->ssl_version);
 	}
 
 	http_200_aliases = curl_slist_append(http_200_aliases, "ICY 200 OK");
diff --git a/src/input/plugins/TidalInputPlugin.cxx b/src/input/plugins/TidalInputPlugin.cxx
index fe8460de0..4a5a1e514 100644
--- a/src/input/plugins/TidalInputPlugin.cxx
+++ b/src/input/plugins/TidalInputPlugin.cxx
@@ -183,7 +183,8 @@ InitTidalInput(EventLoop &event_loop, const ConfigBlock &block)
 	if (password == nullptr)
 		throw PluginUnconfigured("No Tidal password configured");
 
-	FormatWarning(tidal_domain, "The Tidal input plugin is deprecated because Tidal has changed the protocol and doesn't share documentation");
+	LogWarning(tidal_domain,
+		   "The Tidal input plugin is deprecated because Tidal has changed the protocol and doesn't share documentation");
 
 	tidal_audioquality = block.GetBlockValue("audioquality", "HIGH");
 
diff --git a/src/input/plugins/TidalSessionManager.cxx b/src/input/plugins/TidalSessionManager.cxx
index c454429eb..5ee971b9a 100644
--- a/src/input/plugins/TidalSessionManager.cxx
+++ b/src/input/plugins/TidalSessionManager.cxx
@@ -81,7 +81,7 @@ TidalSessionManager::AddLoginHandler(TidalSessionHandler &h) noexcept
 void
 TidalSessionManager::OnTidalLoginSuccess(std::string _session) noexcept
 {
-	FormatDebug(tidal_domain, "Login successful, session=%s", _session.c_str());
+	FmtDebug(tidal_domain, "Login successful, session={}", _session);
 
 	{
 		const std::lock_guard<Mutex> protect(mutex);
diff --git a/src/lib/alsa/HwSetup.cxx b/src/lib/alsa/HwSetup.cxx
index e7c362484..d2821af78 100644
--- a/src/lib/alsa/HwSetup.cxx
+++ b/src/lib/alsa/HwSetup.cxx
@@ -235,9 +235,9 @@ SetupHw(snd_pcm_t *pcm,
 	unsigned buffer_time_min, buffer_time_max;
 	snd_pcm_hw_params_get_buffer_time_min(hwparams, &buffer_time_min, nullptr);
 	snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time_max, nullptr);
-	FormatDebug(alsa_output_domain, "buffer: size=%u..%u time=%u..%u",
-		    (unsigned)buffer_size_min, (unsigned)buffer_size_max,
-		    buffer_time_min, buffer_time_max);
+	FmtDebug(alsa_output_domain, "buffer: size={}..{} time={}..{}",
+		 buffer_size_min, buffer_size_max,
+		 buffer_time_min, buffer_time_max);
 
 	snd_pcm_uframes_t period_size_min, period_size_max;
 	snd_pcm_hw_params_get_period_size_min(hwparams, &period_size_min, nullptr);
@@ -245,9 +245,9 @@ SetupHw(snd_pcm_t *pcm,
 	unsigned period_time_min, period_time_max;
 	snd_pcm_hw_params_get_period_time_min(hwparams, &period_time_min, nullptr);
 	snd_pcm_hw_params_get_period_time_max(hwparams, &period_time_max, nullptr);
-	FormatDebug(alsa_output_domain, "period: size=%u..%u time=%u..%u",
-		    (unsigned)period_size_min, (unsigned)period_size_max,
-		    period_time_min, period_time_max);
+	FmtDebug(alsa_output_domain, "period: size={}..{} time={}..{}",
+		 period_size_min, period_size_max,
+		 period_time_min, period_time_max);
 
 	if (buffer_time > 0) {
 		err = snd_pcm_hw_params_set_buffer_time_near(pcm, hwparams,
@@ -265,9 +265,9 @@ SetupHw(snd_pcm_t *pcm,
 	if (period_time_ro == 0 && buffer_time >= 10000) {
 		period_time_ro = period_time = buffer_time / 4;
 
-		FormatDebug(alsa_output_domain,
-			    "default period_time = buffer_time/4 = %u/4 = %u",
-			    buffer_time, period_time);
+		FmtDebug(alsa_output_domain,
+			 "default period_time = buffer_time/4 = {}/4 = {}",
+			 buffer_time, period_time);
 	}
 
 	if (period_time_ro > 0) {
diff --git a/src/lib/alsa/meson.build b/src/lib/alsa/meson.build
index cf47a012b..7391b2bbd 100644
--- a/src/lib/alsa/meson.build
+++ b/src/lib/alsa/meson.build
@@ -20,6 +20,7 @@ alsa = static_library(
   include_directories: inc,
   dependencies: [
     libasound_dep,
+    log_dep,
   ],
 )
 
diff --git a/src/mixer/plugins/OssMixerPlugin.cxx b/src/mixer/plugins/OssMixerPlugin.cxx
index a84188d03..fbd30540d 100644
--- a/src/mixer/plugins/OssMixerPlugin.cxx
+++ b/src/mixer/plugins/OssMixerPlugin.cxx
@@ -153,9 +153,9 @@ OssMixer::GetVolume()
 	right = (level & 0xff00) >> 8;
 
 	if (left != right) {
-		FormatWarning(oss_mixer_domain,
-			      "volume for left and right is not the same, \"%i\" and "
-			      "\"%i\"\n", left, right);
+		FmtWarning(oss_mixer_domain,
+			   "volume for left and right is not the same, \"{}\" and "
+			   "\"{}\"\n", left, right);
 	}
 
 	return left;
diff --git a/src/output/State.cxx b/src/output/State.cxx
index c2cd54c03..0e1733d44 100644
--- a/src/output/State.cxx
+++ b/src/output/State.cxx
@@ -70,8 +70,8 @@ audio_output_state_read(const char *line, MultipleOutputs &outputs)
 	name = endptr + 1;
 	auto *ao = outputs.FindByName(name);
 	if (ao == nullptr) {
-		FormatDebug(output_domain,
-			    "Ignoring device state for '%s'", name);
+		FmtDebug(output_domain,
+			 "Ignoring device state for '{}'", name);
 		return true;
 	}
 
diff --git a/src/output/plugins/AoOutputPlugin.cxx b/src/output/plugins/AoOutputPlugin.cxx
index bf86bb4c4..367fc5cf7 100644
--- a/src/output/plugins/AoOutputPlugin.cxx
+++ b/src/output/plugins/AoOutputPlugin.cxx
@@ -123,8 +123,8 @@ AoOutput::AoOutput(const ConfigBlock &block)
 	if (ai == nullptr)
 		throw std::runtime_error("problems getting driver info");
 
-	FormatDebug(ao_output_domain, "using ao driver \"%s\" for \"%s\"\n",
-		    ai->short_name, block.GetBlockValue("name", nullptr));
+	FmtDebug(ao_output_domain, "using ao driver \"{}\" for \"{}\"\n",
+		 ai->short_name, block.GetBlockValue("name", nullptr));
 
 	value = block.GetBlockValue("options", nullptr);
 	if (value != nullptr) {
diff --git a/src/output/plugins/FifoOutputPlugin.cxx b/src/output/plugins/FifoOutputPlugin.cxx
index 8727cb4e1..ed42f7d74 100644
--- a/src/output/plugins/FifoOutputPlugin.cxx
+++ b/src/output/plugins/FifoOutputPlugin.cxx
@@ -90,8 +90,8 @@ FifoOutput::FifoOutput(const ConfigBlock &block)
 inline void
 FifoOutput::Delete()
 {
-	FormatDebug(fifo_output_domain,
-		    "Removing FIFO \"%s\"", path_utf8.c_str());
+	FmtDebug(fifo_output_domain,
+		 "Removing FIFO \"{}\"", path_utf8);
 
 	try {
 		RemoveFile(path);
diff --git a/src/output/plugins/HaikuOutputPlugin.cxx b/src/output/plugins/HaikuOutputPlugin.cxx
index 272fb816e..d2d6fc807 100644
--- a/src/output/plugins/HaikuOutputPlugin.cxx
+++ b/src/output/plugins/HaikuOutputPlugin.cxx
@@ -96,7 +96,7 @@ initialize_application()
 	// TODO: actually Run() it and handle B_QUIT_REQUESTED
 	// TODO: use some locking?
 	if (be_app == NULL) {
-		FormatDebug(haiku_output_domain, "creating be_app\n");
+		LogDebug(haiku_output_domain, "creating be_app");
 		new BApplication("application/x-vnd.MusicPD");
 	}
 }
@@ -107,7 +107,7 @@ finalize_application()
 	// TODO: use some locking?
 	delete be_app;
 	be_app = NULL;
-	FormatDebug(haiku_output_domain, "deleting be_app\n");
+	LogDebug(haiku_output_domain, "deleting be_app");
 }
 
 static bool
@@ -163,19 +163,18 @@ HaikuOutput::FillBuffer(void* _buffer, size_t size,
 	release_sem(new_buffer);
 	acquire_sem(buffer_done);
 	bigtime_t w = system_time() - start;
-	
+
 	if (w > 5000LL) {
-		FormatDebug(haiku_output_domain,
-			"haiku:fill_buffer waited %Ldus\n", w);
+		FmtDebug(haiku_output_domain,
+			"haiku:fill_buffer waited {}us", w);
 	}
-	
+
 	if (buffer_filled < buffer_size) {
 		memset(buffer + buffer_filled, 0,
 			buffer_size - buffer_filled);
-		FormatDebug(haiku_output_domain,
-			"haiku:fill_buffer filled %d size %d clearing remainder\n",
-			(int)buffer_filled, (int)buffer_size);
-
+		FmtDebug(haiku_output_domain,
+			 "haiku:fill_buffer filled {} size {} clearing remainder",
+			 buffer_filled, buffer_size);
 	}
 }
 
@@ -222,12 +221,12 @@ HaikuOutput::Open(AudioFormat &audio_format)
 			format.channel_count, format.format,
 			format.frame_rate, B_UNKNOWN_BUS) * 2;
 
-	FormatDebug(haiku_output_domain,
-		"using haiku driver ad: bs: %d ws: %d "
-		"channels %d rate %f fmt %08lx bs %d\n",
-			(int)buffer_size, (int)write_size,
-			(int)format.channel_count, format.frame_rate,
-			format.format, (int)format.buffer_size);
+	FmtDebug(haiku_output_domain,
+		 "using haiku driver ad: bs: {} ws: {} "
+		 "channels {} rate {} fmt {:08x} bs {}",
+		 buffer_size, write_size,
+		 format.channel_count, format.frame_rate,
+		 format.format, format.buffer_size);
 
 	sound_player = new BSoundPlayer(&format, "MPD Output",
 		HaikuOutput::_FillBuffer, NULL, this);
@@ -247,8 +246,7 @@ HaikuOutput::Open(AudioFormat &audio_format)
 	buffer_delay *= 1000 / format.frame_rate;
 	// half of the total buffer play time
 	buffer_delay /= 2;
-	FormatDebug(haiku_output_domain,
-		"buffer delay: %d ms\n", buffer_delay);
+	FmtDebug(haiku_output_domain, "buffer delay: {} ms", buffer_delay);
 
 	new_buffer = create_sem(0, "New buffer request");
 	buffer_done = create_sem(0, "Buffer done");
@@ -303,8 +301,8 @@ HaikuOutput::Delay() const noexcept
 {
 	unsigned delay = buffer_filled ? 0 : buffer_delay;
 
-	//FormatDebug(haiku_output_domain,
-	//		"delay=%d\n", delay / 2);
+	//FmtDebug(haiku_output_domain,
+	//		"delay={}", delay / 2);
 	// XXX: doesn't work
 	//return (delay / 2) ? 1 : 0;
 	(void)delay;
@@ -393,8 +391,9 @@ HaikuOutput::SendTag(const Tag &tag)
 		case TAG_MUSICBRAINZ_ALBUMARTISTID:
 		case TAG_MUSICBRAINZ_TRACKID:
 		default:
-			FormatDebug(haiku_output_domain,
-				"tag item: type %d value '%s'\n", item.type, item.value);
+			FmtDebug(haiku_output_domain,
+				 "tag item: type {} value '{}'\n",
+				 item.type, item.value);
 			break;
 		}
 	}
diff --git a/src/output/plugins/JackOutputPlugin.cxx b/src/output/plugins/JackOutputPlugin.cxx
index b0cb910d6..add47a742 100644
--- a/src/output/plugins/JackOutputPlugin.cxx
+++ b/src/output/plugins/JackOutputPlugin.cxx
@@ -242,9 +242,9 @@ JackOutput::JackOutput(const ConfigBlock &block)
 		/* compatibility with MPD < 0.16 */
 		value = block.GetBlockValue("ports", nullptr);
 		if (value != nullptr)
-			FormatWarning(jack_output_domain,
-				      "deprecated option 'ports' in line %d",
-				      block.line);
+			FmtWarning(jack_output_domain,
+				   "deprecated option 'ports' in line {}",
+				   block.line);
 	}
 
 	if (value != nullptr) {
@@ -258,11 +258,11 @@ JackOutput::JackOutput(const ConfigBlock &block)
 
 	if (num_destination_ports > 0 &&
 	    num_destination_ports != num_source_ports)
-		FormatWarning(jack_output_domain,
-			      "number of source ports (%u) mismatches the "
-			      "number of destination ports (%u) in line %d",
-			      num_source_ports, num_destination_ports,
-			      block.line);
+		FmtWarning(jack_output_domain,
+			   "number of source ports ({}) mismatches the "
+			   "number of destination ports ({}) in line {}",
+			   num_source_ports, num_destination_ports,
+			   block.line);
 
 	ringbuffer_size = block.GetPositiveValue("ringbuffer_size", 32768U);
 }
@@ -543,10 +543,9 @@ JackOutput::Start()
 		for (num_dports = 0; num_dports < MAX_PORTS &&
 			     jports[num_dports] != nullptr;
 		     ++num_dports) {
-			FormatDebug(jack_output_domain,
-				    "destination_port[%u] = '%s'\n",
-				    num_dports,
-				    jports[num_dports]);
+			FmtDebug(jack_output_domain,
+				 "destination_port[{}] = '{}'\n",
+				 num_dports, jports[num_dports]);
 			dports[num_dports] = jports[num_dports];
 		}
 	} else {
diff --git a/src/output/plugins/OSXOutputPlugin.cxx b/src/output/plugins/OSXOutputPlugin.cxx
index be8fa8b27..c8eb1da23 100644
--- a/src/output/plugins/OSXOutputPlugin.cxx
+++ b/src/output/plugins/OSXOutputPlugin.cxx
@@ -258,9 +258,10 @@ osx_output_parse_channel_map(const char *device_name,
 
 			channel_map_str = endptr;
 			want_number = false;
-			FormatDebug(osx_output_domain,
-				"%s: channel_map[%u] = %d",
-				device_name, inserted_channels, channel_map[inserted_channels]);
+			FmtDebug(osx_output_domain,
+				 "{}: channel_map[{}] = {}",
+				 device_name, inserted_channels,
+				 channel_map[inserted_channels]);
 			++inserted_channels;
 			continue;
 		}
@@ -421,10 +422,10 @@ osx_output_set_device_format(AudioDeviceID dev_id,
 
 			// print all (linear pcm) formats and their rating
 			if (score > 0.0f)
-				FormatDebug(osx_output_domain,
-					    "Format: %s rated %f",
-					    StreamDescriptionToString(format_desc).c_str(),
-					    (double)score);
+				FmtDebug(osx_output_domain,
+					 "Format: {} rated {}",
+					 StreamDescriptionToString(format_desc).c_str(),
+					 score);
 
 			if (score > output_score) {
 				output_score  = score;
@@ -498,14 +499,14 @@ osx_output_hog_device(AudioDeviceID dev_id, bool hog) noexcept
 
 	if (hog) {
 		if (hog_pid != -1) {
-			FormatDebug(osx_output_domain,
-				    "Device is already hogged.");
+			LogDebug(osx_output_domain,
+				 "Device is already hogged");
 			return;
 		}
 	} else {
 		if (hog_pid != getpid()) {
-			FormatDebug(osx_output_domain,
-				    "Device is not owned by this process.");
+			FmtDebug(osx_output_domain,
+				 "Device is not owned by this process");
 			return;
 		}
 	}
@@ -520,9 +521,8 @@ osx_output_hog_device(AudioDeviceID dev_id, bool hog) noexcept
 					 size,
 					 &hog_pid);
 	if (err != noErr) {
-		FormatDebug(osx_output_domain,
-			    "Cannot hog the device: %d",
-			    err);
+		FmtDebug(osx_output_domain,
+			 "Cannot hog the device: {}", err);
 	} else {
 		LogDebug(osx_output_domain,
 			 hog_pid == -1
@@ -585,16 +585,16 @@ osx_output_set_device(OSXOutput *oo)
 
 	const auto id = FindAudioDeviceByName(oo->device_name);
 
-	FormatDebug(osx_output_domain,
-		    "found matching device: ID=%u, name=%s",
-		    (unsigned)id, oo->device_name);
+	FmtDebug(osx_output_domain,
+		 "found matching device: ID={}, name={}",
+		 id, oo->device_name);
 
 	AudioUnitSetCurrentDevice(oo->au, id);
 
 	oo->dev_id = id;
-	FormatDebug(osx_output_domain,
-		    "set OS X audio output device ID=%u, name=%s",
-		    (unsigned)id, oo->device_name);
+	FmtDebug(osx_output_domain,
+		 "set OS X audio output device ID={}, name={}",
+		 id, oo->device_name);
 
 	if (oo->channel_map)
 		osx_output_set_channel_map(oo);
diff --git a/src/output/plugins/OssOutputPlugin.cxx b/src/output/plugins/OssOutputPlugin.cxx
index 4ed79e52f..4f65d95db 100644
--- a/src/output/plugins/OssOutputPlugin.cxx
+++ b/src/output/plugins/OssOutputPlugin.cxx
@@ -200,16 +200,16 @@ oss_open_default()
 			/* never reached */
 			break;
 		case OSS_STAT_DOESN_T_EXIST:
-			FormatWarning(oss_output_domain,
-				      "%s not found", dev);
+			FmtWarning(oss_output_domain,
+				   "{} not found", dev);
 			break;
 		case OSS_STAT_NOT_CHAR_DEV:
-			FormatWarning(oss_output_domain,
-				      "%s is not a character device", dev);
+			FmtWarning(oss_output_domain,
+				   "{} is not a character device", dev);
 			break;
 		case OSS_STAT_NO_PERMS:
-			FormatWarning(oss_output_domain,
-				      "%s: permission denied", dev);
+			FmtWarning(oss_output_domain,
+				   "{}: permission denied", dev);
 			break;
 		case OSS_STAT_OTHER:
 			FormatErrno(oss_output_domain, err[i],
diff --git a/src/output/plugins/RecorderOutputPlugin.cxx b/src/output/plugins/RecorderOutputPlugin.cxx
index 29c138779..2de03cbf0 100644
--- a/src/output/plugins/RecorderOutputPlugin.cxx
+++ b/src/output/plugins/RecorderOutputPlugin.cxx
@@ -19,6 +19,7 @@
 
 #include "RecorderOutputPlugin.hxx"
 #include "../OutputAPI.hxx"
+#include "lib/fmt/PathFormatter.hxx"
 #include "tag/Format.hxx"
 #include "encoder/ToOutputStream.hxx"
 #include "encoder/EncoderInterface.hxx"
@@ -276,8 +277,7 @@ RecorderOutput::ReopenFormat(AllocatedPath &&new_path)
 	path = std::move(new_path);
 	file = new_file;
 
-	FormatDebug(recorder_domain, "Recording to \"%s\"",
-		    path.ToUTF8().c_str());
+	FmtDebug(recorder_domain, "Recording to \"{}\"", path);
 }
 
 void
diff --git a/src/output/plugins/ShoutOutputPlugin.cxx b/src/output/plugins/ShoutOutputPlugin.cxx
index 4900172b5..83402083e 100644
--- a/src/output/plugins/ShoutOutputPlugin.cxx
+++ b/src/output/plugins/ShoutOutputPlugin.cxx
@@ -282,9 +282,9 @@ ShoutOutput::Close() noexcept
 
 	if (shout_get_connected(shout_conn) != SHOUTERR_UNCONNECTED &&
 	    shout_close(shout_conn) != SHOUTERR_SUCCESS) {
-		FormatWarning(shout_output_domain,
-			      "problem closing connection to shout server: %s",
-			      shout_get_error(shout_conn));
+		FmtWarning(shout_output_domain,
+			   "problem closing connection to shout server: {}",
+			   shout_get_error(shout_conn));
 	}
 }
 
diff --git a/src/output/plugins/httpd/HttpdClient.cxx b/src/output/plugins/httpd/HttpdClient.cxx
index 175394b28..e7e54120f 100644
--- a/src/output/plugins/httpd/HttpdClient.cxx
+++ b/src/output/plugins/httpd/HttpdClient.cxx
@@ -171,9 +171,9 @@ HttpdClient::SendResponse() noexcept
 	ssize_t nbytes = GetSocket().Write(response, strlen(response));
 	if (gcc_unlikely(nbytes < 0)) {
 		const SocketErrorMessage msg;
-		FormatWarning(httpd_output_domain,
-			      "failed to write to client: %s",
-			      (const char *)msg);
+		FmtWarning(httpd_output_domain,
+			   "failed to write to client: {}",
+			   (const char *)msg);
 		LockClose();
 		return false;
 	}
@@ -284,9 +284,9 @@ HttpdClient::TryWrite() noexcept
 
 				if (!IsSocketErrorClosed(e)) {
 					SocketErrorMessage msg(e);
-					FormatWarning(httpd_output_domain,
-						      "failed to write to client: %s",
-						      (const char *)msg);
+					FmtWarning(httpd_output_domain,
+						   "failed to write to client: {}",
+						   (const char *)msg);
 				}
 
 				Close();
@@ -311,9 +311,9 @@ HttpdClient::TryWrite() noexcept
 
 				if (!IsSocketErrorClosed(e)) {
 					SocketErrorMessage msg(e);
-					FormatWarning(httpd_output_domain,
-						      "failed to write to client: %s",
-						      (const char *)msg);
+					FmtWarning(httpd_output_domain,
+						   "failed to write to client: {}",
+						   (const char *)msg);
 				}
 
 				Close();
@@ -334,9 +334,9 @@ HttpdClient::TryWrite() noexcept
 
 			if (!IsSocketErrorClosed(e)) {
 				SocketErrorMessage msg(e);
-				FormatWarning(httpd_output_domain,
-					      "failed to write to client: %s",
-					      (const char *)msg);
+				FmtWarning(httpd_output_domain,
+					   "failed to write to client: {}",
+					   (const char *)msg);
 			}
 
 			Close();
@@ -370,8 +370,8 @@ HttpdClient::PushPage(PagePtr page) noexcept
 		return;
 
 	if (queue_size > 256 * 1024) {
-		FormatDebug(httpd_output_domain,
-			    "client is too slow, flushing its queue");
+		LogDebug(httpd_output_domain,
+			 "client is too slow, flushing its queue");
 		ClearQueue();
 	}
 
diff --git a/src/output/plugins/wasapi/WasapiOutputPlugin.cxx b/src/output/plugins/wasapi/WasapiOutputPlugin.cxx
index 367f84ce7..9b315fc1c 100644
--- a/src/output/plugins/wasapi/WasapiOutputPlugin.cxx
+++ b/src/output/plugins/wasapi/WasapiOutputPlugin.cxx
@@ -26,6 +26,7 @@
 #include "PropertyStore.hxx"
 #include "output/OutputAPI.hxx"
 #include "lib/icu/Win32.hxx"
+#include "lib/fmt/AudioFormatFormatter.hxx"
 #include "mixer/MixerList.hxx"
 #include "output/Error.hxx"
 #include "pcm/Export.hxx"
@@ -824,13 +825,12 @@ WasapiOutput::TryFormatExclusive(const AudioFormat &audio_format)
 		HRESULT result = client->IsFormatSupported(
 			AUDCLNT_SHAREMODE_EXCLUSIVE,
 			reinterpret_cast<WAVEFORMATEX *>(&test_format), nullptr);
-		const auto format_string = ToString(audio_format);
 		const auto result_string = std::string(HRESULTToString(result));
-		FormatDebug(wasapi_output_domain, "Trying %s %lu %u-%u (exclusive) -> %s",
-			    format_string.c_str(), test_format.Format.nSamplesPerSec,
-			    test_format.Format.wBitsPerSample,
-			    test_format.Samples.wValidBitsPerSample,
-			    result_string.c_str());
+		FmtDebug(wasapi_output_domain, "Trying {} {} {}-{} (exclusive) -> {}",
+			 audio_format, test_format.Format.nSamplesPerSec,
+			 test_format.Format.wBitsPerSample,
+			 test_format.Samples.wValidBitsPerSample,
+			 result_string);
 		if (SUCCEEDED(result)) {
 			device_format = test_format;
 			return true;
@@ -922,13 +922,12 @@ WasapiOutput::FindSharedFormatSupported(AudioFormat &audio_format)
 		reinterpret_cast<WAVEFORMATEX *>(&device_format),
 		closest_format.AddressCast<WAVEFORMATEX>());
 	{
-		const auto format_string = ToString(audio_format);
 		const auto result_string = std::string(HRESULTToString(result));
-		FormatDebug(wasapi_output_domain, "Trying %s %lu %u-%u (shared) -> %s",
-			    format_string.c_str(), device_format.Format.nSamplesPerSec,
-			    device_format.Format.wBitsPerSample,
-			    device_format.Samples.wValidBitsPerSample,
-			    result_string.c_str());
+		FmtDebug(wasapi_output_domain, "Trying {} {} {}-{} (shared) -> {}",
+			 audio_format, device_format.Format.nSamplesPerSec,
+			 device_format.Format.wBitsPerSample,
+			 device_format.Samples.wValidBitsPerSample,
+			 result_string);
 	}
 
 	if (FAILED(result) && result != AUDCLNT_E_UNSUPPORTED_FORMAT) {
@@ -950,15 +949,14 @@ WasapiOutput::FindSharedFormatSupported(AudioFormat &audio_format)
 			reinterpret_cast<WAVEFORMATEX *>(&device_format),
 			closest_format.AddressCast<WAVEFORMATEX>());
 		{
-			const auto format_string = ToString(audio_format);
 			const auto result_string = std::string(HRESULTToString(result));
-			FormatDebug(wasapi_output_domain,
-				    "Trying %s %lu %u-%u (shared) -> %s",
-				    format_string.c_str(),
-				    device_format.Format.nSamplesPerSec,
-				    device_format.Format.wBitsPerSample,
-				    device_format.Samples.wValidBitsPerSample,
-				    result_string.c_str());
+			FmtDebug(wasapi_output_domain,
+				 "Trying {} {} {}-{} (shared) -> {}",
+				 audio_format,
+				 device_format.Format.nSamplesPerSec,
+				 device_format.Format.wBitsPerSample,
+				 device_format.Samples.wValidBitsPerSample,
+				 result_string);
 		}
 		if (FAILED(result)) {
 			throw MakeHResultError(result, "Format is not supported");
diff --git a/src/pcm/LibsamplerateResampler.cxx b/src/pcm/LibsamplerateResampler.cxx
index cc3c805e3..6b9c23d33 100644
--- a/src/pcm/LibsamplerateResampler.cxx
+++ b/src/pcm/LibsamplerateResampler.cxx
@@ -71,9 +71,9 @@ pcm_resample_lsr_global_init(const ConfigBlock &block)
 		throw FormatRuntimeError("unknown samplerate converter '%s'",
 					 converter);
 
-	FormatDebug(libsamplerate_domain,
-		    "libsamplerate converter '%s'",
-		    src_get_name(lsr_converter));
+	FmtDebug(libsamplerate_domain,
+		 "libsamplerate converter '{}'",
+		 src_get_name(lsr_converter));
 }
 
 AudioFormat
@@ -98,9 +98,9 @@ LibsampleratePcmResampler::Open(AudioFormat &af, unsigned new_sample_rate)
 	memset(&data, 0, sizeof(data));
 
 	data.src_ratio = double(new_sample_rate) / double(af.sample_rate);
-	FormatDebug(libsamplerate_domain,
-		    "setting samplerate conversion ratio to %.2lf",
-		    data.src_ratio);
+	FmtDebug(libsamplerate_domain,
+		 "setting samplerate conversion ratio to {:.2}",
+		 data.src_ratio);
 	src_set_ratio(state, data.src_ratio);
 
 	AudioFormat result = af;
diff --git a/src/pcm/SoxrResampler.cxx b/src/pcm/SoxrResampler.cxx
index f576cd52c..1b8c453e1 100644
--- a/src/pcm/SoxrResampler.cxx
+++ b/src/pcm/SoxrResampler.cxx
@@ -200,9 +200,8 @@ pcm_resample_soxr_global_init(const ConfigBlock &block)
 		soxr_quality = soxr_quality_spec(recipe, 0);
 	}
 
-	FormatDebug(soxr_domain,
-		    "soxr converter '%s'",
-		    soxr_quality_name(recipe));
+	FmtDebug(soxr_domain, "soxr converter '{}'",
+		 soxr_quality_name(recipe));
 
 	const unsigned n_threads = block.GetBlockValue("threads", 1);
 	soxr_runtime = soxr_runtime_spec(n_threads);
@@ -226,7 +225,7 @@ SoxrPcmResampler::Open(AudioFormat &af, unsigned new_sample_rate)
 		throw FormatRuntimeError("soxr initialization has failed: %s",
 					 e);
 
-	FormatDebug(soxr_domain, "soxr engine '%s'", soxr_engine(soxr));
+	FmtDebug(soxr_domain, "soxr engine '{}'", soxr_engine(soxr));
 	if (soxr_use_custom_recipe)
 		FormatDebug(soxr_domain,
 			    "soxr precision=%0.0f, phase_response=%0.2f, "
diff --git a/src/pcm/meson.build b/src/pcm/meson.build
index 75eb5fb19..bebfdc55d 100644
--- a/src/pcm/meson.build
+++ b/src/pcm/meson.build
@@ -69,6 +69,7 @@ pcm = static_library(
     pcm_basic_dep,
     libsamplerate_dep,
     soxr_dep,
+    log_dep,
   ],
 )
 
diff --git a/src/player/CrossFade.cxx b/src/player/CrossFade.cxx
index f76877c01..fa99bea65 100644
--- a/src/player/CrossFade.cxx
+++ b/src/player/CrossFade.cxx
@@ -128,9 +128,9 @@ CrossFadeSettings::Calculate(SignedSongTime total_time,
 		    mixramp_delay <= mixramp_overlap) {
 			chunks = lround((mixramp_overlap - mixramp_delay)
 					/ chunk_duration);
-			FormatDebug(cross_fade_domain,
-				    "will overlap %d chunks, %fs", chunks,
-				    (mixramp_overlap - mixramp_delay).count());
+			FmtDebug(cross_fade_domain,
+				 "will overlap {} chunks, {}s", chunks,
+				 (mixramp_overlap - mixramp_delay).count());
 		}
 	}
 
diff --git a/src/queue/Playlist.cxx b/src/queue/Playlist.cxx
index f4a10b503..f965347a1 100644
--- a/src/queue/Playlist.cxx
+++ b/src/queue/Playlist.cxx
@@ -71,8 +71,8 @@ playlist::QueueSongOrder(PlayerControl &pc, unsigned order) noexcept
 
 	const DetachedSong &song = queue.GetOrder(order);
 
-	FormatDebug(playlist_domain, "queue song %i:\"%s\"",
-		    queued, song.GetURI());
+	FmtDebug(playlist_domain, "queue song {}:\"{}\"",
+		 queued, song.GetURI());
 
 	pc.LockEnqueueSong(std::make_unique<DetachedSong>(song));
 }
@@ -178,7 +178,7 @@ playlist::PlayOrder(PlayerControl &pc, unsigned order)
 
 	const DetachedSong &song = queue.GetOrder(order);
 
-	FormatDebug(playlist_domain, "play %u:\"%s\"", order, song.GetURI());
+	FmtDebug(playlist_domain, "play {}:\"{}\"", order, song.GetURI());
 
 	current = order;
 
diff --git a/src/queue/PlaylistControl.cxx b/src/queue/PlaylistControl.cxx
index b8e77c267..6208959a5 100644
--- a/src/queue/PlaylistControl.cxx
+++ b/src/queue/PlaylistControl.cxx
@@ -36,7 +36,7 @@ playlist::Stop(PlayerControl &pc) noexcept
 
 	assert(current >= 0);
 
-	FormatDebug(playlist_domain, "stop");
+	LogDebug(playlist_domain, "stop");
 	pc.LockStop();
 	queued = -1;
 	playing = false;
diff --git a/src/zeroconf/Bonjour.cxx b/src/zeroconf/Bonjour.cxx
index c8a03083c..146d5c2ab 100644
--- a/src/zeroconf/Bonjour.cxx
+++ b/src/zeroconf/Bonjour.cxx
@@ -79,9 +79,9 @@ BonjourHelper::Callback([[maybe_unused]] DNSServiceRef sdRef,
 
 		helper.Cancel();
 	} else {
-		FormatDebug(bonjour_domain,
-			    "Registered zeroconf service with name '%s'",
-			    name);
+		FmtDebug(bonjour_domain,
+			 "Registered zeroconf service with name '{}'",
+			 name);
 	}
 }