diff --git a/dom/media/encoder/MediaEncoder.cpp b/dom/media/encoder/MediaEncoder.cpp
index a4ce70d62e8e..e9468072877a 100644
--- a/dom/media/encoder/MediaEncoder.cpp
+++ b/dom/media/encoder/MediaEncoder.cpp
@@ -539,7 +539,13 @@ MediaEncoder::ConnectMediaStreamTrack(MediaStreamTrack* aTrack)
     }
 
     mAudioTrack = audio;
-    audio->AddDirectListener(mAudioListener);
+    // With full duplex we don't risk having audio come in late to the MSG
+    // so we won't need a direct listener.
+    const bool enableDirectListener =
+      !Preferences::GetBool("media.navigator.audio.full_duplex", false);
+    if (enableDirectListener) {
+      audio->AddDirectListener(mAudioListener);
+    }
     audio->AddListener(mAudioListener);
   } else if (VideoStreamTrack* video = aTrack->AsVideoStreamTrack()) {
     if(!mVideoEncoder) {