diff --git a/android/a2dp.c b/android/a2dp.c
index c12d8f1..38384f6 100644
--- a/android/a2dp.c
+++ b/android/a2dp.c
@@ -354,7 +354,16 @@ static sdp_record_t *a2dp_record(void)
 	return record;
 }
 
+static void bt_audio_open(const void *buf, uint16_t len)
+{
+	DBG("Not Implemented");
+
+	audio_ipc_send_rsp(AUDIO_OP_OPEN, AUDIO_STATUS_FAILED);
+}
+
 static const struct ipc_handler audio_handlers[] = {
+	/* AUDIO_OP_OPEN */
+	{ bt_audio_open, true, sizeof(struct audio_cmd_open) },
 };
 
 bool bt_a2dp_register(const bdaddr_t *addr)
diff --git a/android/audio-ipc-api.txt b/android/audio-ipc-api.txt
index 1c42800..37a1569 100644
--- a/android/audio-ipc-api.txt
+++ b/android/audio-ipc-api.txt
@@ -49,9 +49,9 @@ Identifier: "audio" (BT_AUDIO_ID)
 
 		Command parameters: Service UUID (16 octets)
 				    Codec ID (1 octet)
+				    Number of codec presets (1 octet)
 				    Codec capabilities length (1 octet)
 				    Codec capabilities (variable)
-				    Number of codec presets (1 octet)
 				    Codec preset # length (1 octet)
 				    Codec preset # configuration (variable)
 				    ...
diff --git a/android/audio-msg.h b/android/audio-msg.h
index ae8a168..158a2ab 100644
--- a/android/audio-msg.h
+++ b/android/audio-msg.h
@@ -34,3 +34,21 @@ static const char BLUEZ_AUDIO_SK_PATH[] = "\0bluez_audio_socket";
 struct audio_status {
 	uint8_t code;
 } __attribute__((packed));
+
+#define AUDIO_OP_OPEN			0x01
+struct audio_preset {
+	uint8_t len;
+	uint8_t data[0];
+} __attribute__((packed));
+
+struct audio_cmd_open {
+	uint16_t uuid;
+	uint8_t codec;
+	uint8_t presets;
+	uint8_t len;
+	struct audio_preset preset[0];
+} __attribute__((packed));
+
+struct audio_rsp_open {
+	uint8_t id;
+} __attribute__((packed));