diff --git a/services/audiopolicy/AudioPolicyInterface.h b/services/audiopolicy/AudioPolicyInterface.h
index 7cf44dc..c4dee5a 100644
--- a/services/audiopolicy/AudioPolicyInterface.h
+++ b/services/audiopolicy/AudioPolicyInterface.h
@@ -228,6 +228,9 @@
                                       audio_io_handle_t *handle,
                                       uid_t uid) = 0;
     virtual status_t stopAudioSource(audio_io_handle_t handle) = 0;
+
+    virtual status_t setMasterMono(bool mono) = 0;
+    virtual status_t getMasterMono(bool *mono) = 0;
 };