diff --git a/CHANGES.md b/CHANGES.md
index c40cfe7463..185704b242 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -16,6 +16,7 @@ Changed:
 
 Fixed:
 
+- Fixed slow memory leak in muxer operator (#3372, #3181)
 - Fixed discontinuity logic error in HLS outputs after a restart.
 - Fixed HTTP response status in `output.harbor` (#3255)
 - Make sure main HLS playlist is regenerated after being
diff --git a/src/core/operators/muxer.ml b/src/core/operators/muxer.ml
index 4f4841c4f2..6bf8d603c3 100644
--- a/src/core/operators/muxer.ml
+++ b/src/core/operators/muxer.ml
@@ -159,7 +159,7 @@ class muxer tracks =
     initializer
       self#on_after_output (fun () ->
           clear_track_frames ();
-          Frame.clear self#buffer)
+          Generator.clear self#buffer)
   end
 
 let muxer_operator p =
diff --git a/tests/streams/dtmf.liq b/tests/streams/dtmf.liq
index bd78e782d6..2f4ed523d1 100755
--- a/tests/streams/dtmf.liq
+++ b/tests/streams/dtmf.liq
@@ -19,7 +19,7 @@ def f(k)
   end
 end
 
-s = amplify(0.5, dtmf(duration=0.1, keys))
+s = amplify(0.5, dtmf(duration=1., keys))
 # s = add([s, amplify(0.5, noise())]) # Removed to make the test deterministic
 s = dtmf.detect(debug=false, s, f)
 
diff --git a/tests/streams/dtmf_pcm_s16.liq b/tests/streams/dtmf_pcm_s16.liq
index 5cadb8d388..7a399899c4 100755
--- a/tests/streams/dtmf_pcm_s16.liq
+++ b/tests/streams/dtmf_pcm_s16.liq
@@ -18,7 +18,7 @@ def f(k)
   end
 end
 
-s = amplify(0.5, dtmf(duration=0.1, keys))
+s = amplify(0.5, dtmf(duration=1., keys))
 s = audio.encode.pcm_s16(s)
 s = add([s, blank()])
 s = audio.decode.pcm_s16(s)