diff --git a/src/modules/muorb/adsp/uORBFastRpcChannel.cpp b/src/modules/muorb/adsp/uORBFastRpcChannel.cpp
index f730316a19..76034b88c0 100644
--- a/src/modules/muorb/adsp/uORBFastRpcChannel.cpp
+++ b/src/modules/muorb/adsp/uORBFastRpcChannel.cpp
@@ -71,21 +71,31 @@ uORB::FastRpcChannel::FastRpcChannel()
 //==============================================================================
 //==============================================================================
 int16_t uORB::FastRpcChannel::topic_advertised(const char *messageName)
+{
+	return control_msg_queue_add(_CONTROL_MSG_TYPE_ADVERTISE, messageName);
+}
+
+//==============================================================================
+//==============================================================================
+int16_t uORB::FastRpcChannel::topic_unadvertised(const char *messageName)
+{
+	return control_msg_queue_add(_CONTROL_MSG_TYPE_UNADVERTISE, messageName);
+}
+
+//==============================================================================
+//==============================================================================
+int16_t uORB::FastRpcChannel::control_msg_queue_add(int32_t msgtype, const char *messageName)
 {
 	int16_t rc = 0;
 	hrt_abstime t1, t2;
 	static hrt_abstime check_time = 0;
 
-	PX4_DEBUG("=========publish topic[%s] to remote...", messageName);
-
 	t1 = hrt_absolute_time();
 	_QueueMutex.lock();
 	bool overwriteData = false;
 
 	if (IsControlQFull()) {
 		// queue is full.  Overwrite the oldest data.
-		//PX4_WARN("[topic_advertised] Queue Full Overwrite the oldest data. in[%ld] out[%ld] max[%ld]",
-		//	 _ControlQInIndex, _ControlQOutIndex, _MAX_MSG_QUEUE_SIZE);
 		_ControlQOutIndex++;
 
 		if (_ControlQOutIndex == _MAX_MSG_QUEUE_SIZE) {
@@ -96,7 +106,7 @@ int16_t uORB::FastRpcChannel::topic_advertised(const char *messageName)
 		_dropped_pkts++;
 	}
 
-	_ControlMsgQueue[ _ControlQInIndex ]._Type = _CONTROL_MSG_TYPE_ADVERTISE;
+	_ControlMsgQueue[ _ControlQInIndex ]._Type = msgtype;
 	_ControlMsgQueue[ _ControlQInIndex ]._MsgName = messageName;
 
 	_ControlQInIndex++;
@@ -106,7 +116,6 @@ int16_t uORB::FastRpcChannel::topic_advertised(const char *messageName)
 	}
 
 	// the assumption here is that each caller reads only one data from either control or data queue.
-	//if (!overwriteData) {
 	if (ControlQSize() == 1 && DataQSize() == 0) {  // post it only of the queue moves from empty to available.
 		_DataAvailableSemaphore.post();
 	}
@@ -134,19 +143,6 @@ int16_t uORB::FastRpcChannel::topic_advertised(const char *messageName)
 	return rc;
 }
 
-//==============================================================================
-//==============================================================================
-/*
-//TODO: verify if needed
-int16_t uORB::FastRpcChannel::topic_unadvertised(const char *messageName)
-{
-	int16_t rc = 0;
-
-	PX4_DEBUG("=========unpublish topic[%s] to remote...", messageName);
-	return rc;
-}
-*/
-
 //==============================================================================
 //==============================================================================
 int16_t uORB::FastRpcChannel::add_subscription(const char *messageName, int32_t msgRateInHz)
diff --git a/src/modules/muorb/adsp/uORBFastRpcChannel.hpp b/src/modules/muorb/adsp/uORBFastRpcChannel.hpp
index 194e4936bd..fe5f686c14 100644
--- a/src/modules/muorb/adsp/uORBFastRpcChannel.hpp
+++ b/src/modules/muorb/adsp/uORBFastRpcChannel.hpp
@@ -82,7 +82,7 @@ public:
 	 * 		Note: This does not mean that the receiver as received it.
 	 *  otherwise = failure.
 	 */
-	//virtual int16_t topic_unadvertised(const char *messageName);
+	virtual int16_t topic_unadvertised(const char *messageName);
 
 	/**
 	 * @brief Interface to notify the remote entity of interest of a
@@ -183,6 +183,7 @@ private: // data members
 	static const int32_t _CONTROL_MSG_TYPE_REMOVE_SUBSCRIBER = 2;
 	static const int32_t _DATA_MSG_TYPE = 3;
 	static const int32_t _CONTROL_MSG_TYPE_ADVERTISE = 4;
+	static const int32_t _CONTROL_MSG_TYPE_UNADVERTISE = 5;
 
 	static const int32_t _PACKET_FIELD_TOPIC_NAME_LEN_SIZE_IN_BYTES = 2;
 	static const int32_t _PACKET_FIELD_DATA_LEN_IN_BYTES = 2;
@@ -292,6 +293,7 @@ private://class members.
 
 	int32_t get_msg_size_at(bool isData, int32_t index);
 	int32_t copy_msg_to_buffer(bool isData, int32_t src_index, uint8_t *dst_buffer, int32_t offset, int32_t dst_buffer_len);
+	int16_t control_msg_queue_add(int32_t msgtype, const char *messageName);
 
 	std::set<std::string> _RemoteSubscribers;
 };
diff --git a/src/modules/muorb/krait/uORBKraitFastRpcChannel.cpp b/src/modules/muorb/krait/uORBKraitFastRpcChannel.cpp
index 2da4c031bf..bb79fc007c 100644
--- a/src/modules/muorb/krait/uORBKraitFastRpcChannel.cpp
+++ b/src/modules/muorb/krait/uORBKraitFastRpcChannel.cpp
@@ -76,8 +76,6 @@ int16_t uORB::KraitFastRpcChannel::topic_advertised(const char *messageName)
 	return rc;
 }
 
-/*
-//TODO: verify if needed
 int16_t uORB::KraitFastRpcChannel::topic_unadvertised(const char *messageName)
 {
 	int16_t rc = 0;
@@ -86,7 +84,6 @@ int16_t uORB::KraitFastRpcChannel::topic_unadvertised(const char *messageName)
 	PX4_DEBUG("Response for TopicUnadvertised for [%s], rc[%d]\n", messageName, rc);
 	return rc;
 }
-*/
 
 int16_t uORB::KraitFastRpcChannel::add_subscription(const char *messageName, int32_t msgRateInHz)
 {
@@ -280,8 +277,11 @@ void uORB::KraitFastRpcChannel::fastrpc_recv_thread()
 						_RxHandler->process_received_message(messageName,
 										 header->_DataLen, topic_data);
 					} else if (header->_MsgType == _CONTROL_MSG_TYPE_ADVERTISE) {
-						PX4_DEBUG( "Received topic for control message for: [%s] len[%d]\n", messageName, data_length );
+						PX4_DEBUG( "Received topic advertise message for: [%s] len[%d]\n", messageName, data_length );
 						_RxHandler->process_remote_topic(messageName, true);
+					} else if (header->_MsgType == _CONTROL_MSG_TYPE_UNADVERTISE) {
+						PX4_DEBUG( "Received topic unadvertise message for: [%s] len[%d]\n", messageName, data_length );
+						_RxHandler->process_remote_topic(messageName, false);
 					}
 				}
 
diff --git a/src/modules/muorb/krait/uORBKraitFastRpcChannel.hpp b/src/modules/muorb/krait/uORBKraitFastRpcChannel.hpp
index 0424475909..25fad8e0ed 100644
--- a/src/modules/muorb/krait/uORBKraitFastRpcChannel.hpp
+++ b/src/modules/muorb/krait/uORBKraitFastRpcChannel.hpp
@@ -95,7 +95,7 @@ public:
 	 * 		Note: This does not mean that the receiver as received it.
 	 *  otherwise = failure.
 	 */
-	//virtual int16_t topic_unadvertised(const char *messageName);
+	virtual int16_t topic_unadvertised(const char *messageName);
 
 	/**
 	 * @brief Interface to notify the remote entity of interest of a
@@ -168,6 +168,7 @@ private: // data members
 	static const int32_t _CONTROL_MSG_TYPE_REMOVE_SUBSCRIBER = 2;
 	static const int32_t _DATA_MSG_TYPE = 3;
 	static const int32_t _CONTROL_MSG_TYPE_ADVERTISE = 4;
+	static const int32_t _CONTROL_MSG_TYPE_UNADVERTISE = 5;
 
 	struct BulkTransferHeader {
 		uint16_t _MsgType;