diff --git a/src/output/Filtered.hxx b/src/output/Filtered.hxx
index 4482fddb0..8219896a6 100644
--- a/src/output/Filtered.hxx
+++ b/src/output/Filtered.hxx
@@ -181,7 +181,8 @@ public:
 	void Disable() noexcept;
 
 	/**
-	 * Invoke OutputPlugin::close().
+	 * Close everything: the output (via CloseOutput()) and the
+	 * software mixer (via CloseSoftwareMixer()).
 	 *
 	 * Caller must not lock the mutex.
 	 */
@@ -200,7 +201,7 @@ public:
 	void OpenOutputAndConvert(AudioFormat audio_format);
 
 	/**
-	 * Close the output plugin.
+	 * Invoke AudioOutput::Close(), but nothing else.
 	 *
 	 * Mutex must not be locked.
 	 */