diff --git a/NEWS b/NEWS
index 1c6a2ed72..6709515f9 100644
--- a/NEWS
+++ b/NEWS
@@ -19,8 +19,11 @@ ver 0.24 (not yet released)
 * remove Haiku support
 
 ver 0.23.9 (not yet released)
+* decoder
+  - ffmpeg: support FFmpeg 5.1
 * output
   - pipewire: set app icon
+* improve iconv detection
 
 ver 0.23.8 (2022/07/09)
 * storage
diff --git a/python/build/libs.py b/python/build/libs.py
index 0fca3daca..3409c63f6 100644
--- a/python/build/libs.py
+++ b/python/build/libs.py
@@ -151,8 +151,8 @@ gme = CmakeProject(
 )
 
 ffmpeg = FfmpegProject(
-    'http://ffmpeg.org/releases/ffmpeg-5.0.1.tar.xz',
-    'ef2efae259ce80a240de48ec85ecb062cecca26e4352ffb3fda562c21a93007b',
+    'http://ffmpeg.org/releases/ffmpeg-5.1.tar.xz',
+    '55eb6aab5ee235550fa54a33eaf8bf1b4ec66c01453182b12f6a993d75698b03',
     'lib/libavcodec.a',
     [
         '--disable-shared', '--enable-static',
@@ -166,7 +166,6 @@ ffmpeg = FfmpegProject(
         '--disable-swscale',
         '--disable-postproc',
         '--disable-avfilter',
-        '--disable-lzo',
         '--disable-faan',
         '--disable-pixelutils',
         '--disable-network',
diff --git a/src/decoder/plugins/FfmpegDecoderPlugin.cxx b/src/decoder/plugins/FfmpegDecoderPlugin.cxx
index 86047f4bf..1f8d1d664 100644
--- a/src/decoder/plugins/FfmpegDecoderPlugin.cxx
+++ b/src/decoder/plugins/FfmpegDecoderPlugin.cxx
@@ -520,9 +520,15 @@ FfmpegDecode(DecoderClient &client, InputStream *input,
 		return;
 	}
 
+#if LIBAVUTIL_VERSION_INT >= AV_VERSION_INT(57, 25, 100)
+	const unsigned channels = codec_context->ch_layout.nb_channels;
+#else
+	const unsigned channels = codec_context->channels;
+#endif
+
 	const auto audio_format = CheckAudioFormat(codec_context->sample_rate,
 						   sample_format,
-						   codec_context->channels);
+						   channels);
 
 	const SignedSongTime total_time =
 		av_stream.duration != (int64_t)AV_NOPTS_VALUE
@@ -632,10 +638,17 @@ FfmpegScanStream(AVFormatContext &format_context, TagHandler &handler)
 						  AV_TIME_BASE_Q));
 
 	const auto &codec_params = *stream.codecpar;
+
+#if LIBAVUTIL_VERSION_INT >= AV_VERSION_INT(57, 25, 100)
+	const unsigned channels = codec_params.ch_layout.nb_channels;
+#else
+	const unsigned channels = codec_params.channels;
+#endif
+
 	try {
 		handler.OnAudioFormat(CheckAudioFormat(codec_params.sample_rate,
 						       ffmpeg_sample_format(AVSampleFormat(codec_params.format)),
-						       codec_params.channels));
+						       channels));
 	} catch (...) {
 	}
 
diff --git a/src/decoder/plugins/FfmpegIo.cxx b/src/decoder/plugins/FfmpegIo.cxx
index ebf544ec4..572f1a86a 100644
--- a/src/decoder/plugins/FfmpegIo.cxx
+++ b/src/decoder/plugins/FfmpegIo.cxx
@@ -21,10 +21,13 @@
 #define __STDC_CONSTANT_MACROS
 
 #include "FfmpegIo.hxx"
-#include "libavutil/mem.h"
 #include "../DecoderAPI.hxx"
 #include "input/InputStream.hxx"
 
+extern "C" {
+#include <libavutil/mem.h>
+}
+
 AvioStream::~AvioStream()
 {
 	if (io != nullptr) {
diff --git a/src/lib/ffmpeg/Interleave.cxx b/src/lib/ffmpeg/Interleave.cxx
index a19319dea..1afa1aa3f 100644
--- a/src/lib/ffmpeg/Interleave.cxx
+++ b/src/lib/ffmpeg/Interleave.cxx
@@ -37,7 +37,11 @@ InterleaveFrame(const AVFrame &frame, FfmpegBuffer &buffer)
 	assert(frame.nb_samples > 0);
 
 	const auto format = AVSampleFormat(frame.format);
+#if LIBAVUTIL_VERSION_INT >= AV_VERSION_INT(57, 25, 100)
+	const unsigned channels = frame.ch_layout.nb_channels;
+#else
 	const unsigned channels = frame.channels;
+#endif
 	const std::size_t n_frames = frame.nb_samples;
 
 	int plane_size;
diff --git a/src/lib/icu/meson.build b/src/lib/icu/meson.build
index 6e489876b..92f9e6b1f 100644
--- a/src/lib/icu/meson.build
+++ b/src/lib/icu/meson.build
@@ -18,17 +18,25 @@ if icu_dep.found()
     'Util.cxx',
     'Init.cxx',
   ]
-elif not get_option('iconv').disabled()
-  # an installed iconv library will make the builtin iconv() unavailable,
-  # so search for the library first and pass it as (possible) dependency
-  iconv_dep = compiler.find_library('libiconv', required: false)
-  have_iconv = compiler.has_function('iconv', 
-    dependencies: iconv_dep, 
-    prefix : '#include <iconv.h>')
-  if not have_iconv and get_option('iconv').enabled()
-    error('iconv() not available')
+else
+  if meson.version().version_compare('>= 0.60')
+    iconv_dep = dependency('iconv', required: get_option('iconv'))
+    conf.set('HAVE_ICONV', iconv_dep.found())
+  elif not get_option('iconv').disabled()
+    iconv_open_snippet = '''#include <iconv.h>
+      int main() {
+      iconv_open("","");
+      }'''
+    have_iconv = compiler.links(iconv_open_snippet, name: 'iconv_open')
+    if not have_iconv
+      iconv_dep = compiler.find_library('iconv', required: false)
+      have_iconv = compiler.links(iconv_open_snippet, dependencies: iconv_dep, name: 'iconv_open')
+    endif
+    if not have_iconv and get_option('iconv').enabled()
+      error('iconv() not available')
+    endif
+    conf.set('HAVE_ICONV', have_iconv)
   endif
-  conf.set('HAVE_ICONV', have_iconv)
 endif
 
 icu = static_library(