diff --git a/services/audioflinger/PlaybackTracks.h b/services/audioflinger/PlaybackTracks.h
index ee2dd9b..374f361 100644
--- a/services/audioflinger/PlaybackTracks.h
+++ b/services/audioflinger/PlaybackTracks.h
@@ -455,7 +455,7 @@
 };  // end of OutputTrack
 
 // playback track, used by PatchPanel
-class PatchTrack : public Track, public PatchTrackBase {
+class PatchTrack : public Track, public PatchTrackBase, public IAfPatchTrack {
 public:
 
                         PatchTrack(PlaybackThread *playbackThread,