diff --git a/NEWS b/NEWS
index 088f23c76..c6e18a8be 100644
--- a/NEWS
+++ b/NEWS
@@ -23,6 +23,8 @@ ver 0.23.9 (not yet released)
   - cdio_paranoia: add options "mode" and "skip"
 * decoder
   - ffmpeg: support FFmpeg 5.1
+* filter
+  - replay gain: fix delayed volume display with handler=mixer
 * output
   - pipewire: set app icon
 * fix bogus volume levels with multiple partitions
diff --git a/src/filter/plugins/ReplayGainFilterPlugin.cxx b/src/filter/plugins/ReplayGainFilterPlugin.cxx
index 91907310b..4840943d9 100644
--- a/src/filter/plugins/ReplayGainFilterPlugin.cxx
+++ b/src/filter/plugins/ReplayGainFilterPlugin.cxx
@@ -23,6 +23,8 @@
 #include "tag/ReplayGainInfo.hxx"
 #include "config/ReplayGainConfig.hxx"
 #include "mixer/MixerControl.hxx"
+#include "mixer/MixerInternal.hxx"
+#include "mixer/Listener.hxx"
 #include "pcm/AudioFormat.hxx"
 #include "pcm/Volume.hxx"
 #include "util/Domain.hxx"
@@ -170,9 +172,11 @@ ReplayGainFilter::Update()
 		try {
 			mixer_set_volume(mixer, _volume);
 
-			/* TODO: emit this idle event only for the
-			   current partition */
-			idle_add(IDLE_MIXER);
+			/* invoke the mixer's listener manually, just
+			   in case the mixer implementation didn't do
+			   that already (this depends on the
+			   implementation) */
+			mixer->listener.OnMixerVolumeChanged(*mixer, _volume);
 		} catch (...) {
 			LogError(std::current_exception(),
 				 "Failed to update hardware mixer");
diff --git a/src/mixer/MixerAll.cxx b/src/mixer/MixerAll.cxx
index 5d528d652..abd0d8462 100644
--- a/src/mixer/MixerAll.cxx
+++ b/src/mixer/MixerAll.cxx
@@ -188,8 +188,8 @@ MultipleOutputs::SetSoftwareVolume(unsigned volume) noexcept
 		auto *mixer = ao->GetMixer();
 
 		if (mixer != nullptr &&
-		    (&mixer->plugin == &software_mixer_plugin ||
-		     &mixer->plugin == &null_mixer_plugin))
+		    (mixer->IsPlugin(software_mixer_plugin) ||
+		     mixer->IsPlugin(null_mixer_plugin)))
 			mixer_set_volume(mixer, volume);
 	}
 }
diff --git a/src/mixer/MixerControl.cxx b/src/mixer/MixerControl.cxx
index 3a4a8331f..b797d4bbe 100644
--- a/src/mixer/MixerControl.cxx
+++ b/src/mixer/MixerControl.cxx
@@ -92,7 +92,7 @@ mixer_close(Mixer *mixer)
 void
 mixer_auto_close(Mixer *mixer)
 {
-	if (!mixer->plugin.global)
+	if (!mixer->IsGlobal())
 		mixer_close(mixer);
 }
 
@@ -103,7 +103,7 @@ mixer_get_volume(Mixer *mixer)
 
 	assert(mixer != nullptr);
 
-	if (mixer->plugin.global && !mixer->failure)
+	if (mixer->IsGlobal() && !mixer->failure)
 		mixer_open(mixer);
 
 	const std::scoped_lock<Mutex> protect(mixer->mutex);
@@ -128,7 +128,7 @@ mixer_set_volume(Mixer *mixer, unsigned volume)
 	assert(mixer != nullptr);
 	assert(volume <= 100);
 
-	if (mixer->plugin.global && !mixer->failure)
+	if (mixer->IsGlobal() && !mixer->failure)
 		mixer_open(mixer);
 
 	const std::scoped_lock<Mutex> protect(mixer->mutex);