diff --git a/include/audiomanager/AudioManager.h b/include/audiomanager/AudioManager.h
index 6794fbf..43048db 100644
--- a/include/audiomanager/AudioManager.h
+++ b/include/audiomanager/AudioManager.h
@@ -40,9 +40,17 @@
     PLAYER_UPDATE_DEVICE_ID = 5,
     PLAYER_UPDATE_PORT_ID = 6,
     PLAYER_UPDATE_MUTED = 7,
+    PLAYER_UPDATE_FORMAT = 8,
 } player_state_t;
 
 static constexpr char
+    kExtraPlayerEventSpatializedKey[] = "android.media.extra.PLAYER_EVENT_SPATIALIZED";
+static constexpr char
+    kExtraPlayerEventSampleRateKey[] = "android.media.extra.PLAYER_EVENT_SAMPLE_RATE";
+static constexpr char
+    kExtraPlayerEventChannelMaskKey[] = "android.media.extra.PLAYER_EVENT_CHANNEL_MASK";
+
+static constexpr char
     kExtraPlayerEventMuteKey[] = "android.media.extra.PLAYER_EVENT_MUTE";
 enum {
     PLAYER_MUTE_MASTER = (1 << 0),