diff --git a/NEWS b/NEWS
index 354491ea5..8c8f514a5 100644
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,7 @@ ver 0.21.11 (not yet released)
   - alsa: fix busy loop while draining
   - alsa: fix missing drain call
   - alsa: improve xrun-avoiding silence generator
+  - alsa: log when generating silence due to slow decoder
   - alsa, osx: fix distortions with DSD_U32 and DoP on 32 bit CPUs
 * protocol
   - fix "list" with multiple "group" levels
diff --git a/src/output/plugins/AlsaOutputPlugin.cxx b/src/output/plugins/AlsaOutputPlugin.cxx
index 7e1919e43..8ccdd2121 100644
--- a/src/output/plugins/AlsaOutputPlugin.cxx
+++ b/src/output/plugins/AlsaOutputPlugin.cxx
@@ -27,6 +27,7 @@
 #include "../OutputAPI.hxx"
 #include "mixer/MixerList.hxx"
 #include "pcm/PcmExport.hxx"
+#include "system/PeriodClock.hxx"
 #include "thread/Mutex.hxx"
 #include "thread/Cond.hxx"
 #include "util/Manual.hxx"
@@ -65,6 +66,8 @@ class AlsaOutput final
 	 */
 	TimerEvent silence_timer;
 
+	PeriodClock throttle_silence_log;
+
 	Manual<PcmExport> pcm_export;
 
 	/**
@@ -1073,6 +1076,9 @@ try {
 			return;
 		}
 
+		if (throttle_silence_log.CheckUpdate(std::chrono::seconds(5)))
+			FormatWarning(alsa_output_domain, "Decoder is too slow; playing silence to avoid xrun");
+
 		/* insert some silence if the buffer has not enough
 		   data yet, to avoid ALSA xrun */
 		period_buffer.FillWithSilence(silence, out_frame_size);