diff --git a/DMRControl.cpp b/DMRControl.cpp
index 57610808..40178bab 100644
--- a/DMRControl.cpp
+++ b/DMRControl.cpp
@@ -50,7 +50,7 @@ bool CDMRControl::processWakeup(const unsigned char* data)
 	assert(data != NULL);
 
 	// Wakeups always come in on slot 1
-	if (data[0U] != TAG_DATA || data[1U] != (DMR_IDLE_RX | DMR_SYNC_DATA | DT_CSBK))
+	if (data[0U] != TAG_DATA1 || data[1U] != (DMR_IDLE_RX | DMR_SYNC_DATA | DT_CSBK))
 		return false;
 
 	CDMRCSBK csbk;
diff --git a/DMRDefines.h b/DMRDefines.h
index 5b53c33d..ca08c19a 100644
--- a/DMRDefines.h
+++ b/DMRDefines.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -19,7 +19,7 @@
 #if !defined(DMRDefines_H)
 #define	DMRDefines_H
 
-#include "Defines.h"		// For TAG_DATA
+#include "Defines.h"		// For TAG_DATA1
 
 const unsigned int DMR_FRAME_LENGTH_BITS  = 264U;
 const unsigned int DMR_FRAME_LENGTH_BYTES = 33U;
@@ -54,13 +54,13 @@ const unsigned char DIRECT_SLOT2_DATA_SYNC[]  = {0x0DU, 0x75U, 0x57U, 0xF5U, 0xF
 const unsigned char SYNC_MASK[]               = {0x0FU, 0xFFU, 0xFFU, 0xFFU, 0xFFU, 0xFFU, 0xF0U};
 
 // The PR FILL and Data Sync pattern.
-const unsigned char DMR_IDLE_DATA[] = {TAG_DATA, 0x00U,
+const unsigned char DMR_IDLE_DATA[] = {TAG_DATA1, 0x00U,
 							0x53U, 0xC2U, 0x5EU, 0xABU, 0xA8U, 0x67U, 0x1DU, 0xC7U, 0x38U, 0x3BU, 0xD9U,
 							0x36U, 0x00U, 0x0DU, 0xFFU, 0x57U, 0xD7U, 0x5DU, 0xF5U, 0xD0U, 0x03U, 0xF6U,
 							0xE4U, 0x65U, 0x17U, 0x1BU, 0x48U, 0xCAU, 0x6DU, 0x4FU, 0xC6U, 0x10U, 0xB4U};
 
 // A silence frame only
-const unsigned char DMR_SILENCE_DATA[] = {TAG_DATA, 0x00U,
+const unsigned char DMR_SILENCE_DATA[] = {TAG_DATA1, 0x00U,
 							0xB9U, 0xE8U, 0x81U, 0x52U, 0x61U, 0x73U, 0x00U, 0x2AU, 0x6BU, 0xB9U, 0xE8U,
 							0x81U, 0x52U, 0x60U, 0x00U, 0x00U, 0x00U, 0x00U, 0x00U, 0x01U, 0x73U, 0x00U,
 							0x2AU, 0x6BU, 0xB9U, 0xE8U, 0x81U, 0x52U, 0x61U, 0x73U, 0x00U, 0x2AU, 0x6BU};
diff --git a/DMRSlot.cpp b/DMRSlot.cpp
index 1f405ca4..374dc400 100644
--- a/DMRSlot.cpp
+++ b/DMRSlot.cpp
@@ -255,7 +255,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			// Convert the Data Sync to be from the BS or MS as needed
 			CSync::addDMRDataSync(data + 2U, m_duplex);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			m_rfTimeoutTimer.start();
@@ -315,7 +315,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			bptc.decode(data + 2U, payload);
 			bptc.encode(payload, data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			if (m_duplex)
@@ -404,7 +404,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			// Convert the Data Sync to be from the BS or MS as needed
 			CSync::addDMRDataSync(data + 2U, m_duplex);
 
-			data[0U] = m_rfFrames == 0U ? TAG_EOT : TAG_DATA;
+			data[0U] = m_rfFrames == 0U ? TAG_EOT : TAG_DATA1;
 			data[1U] = 0x00U;
 
 			if (m_duplex)
@@ -472,7 +472,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			// Convert the Data Sync to be from the BS or MS as needed
 			CSync::addDMRDataSync(data + 2U, m_duplex);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			if (m_duplex)
@@ -545,7 +545,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 
 			m_rfFrames--;
 
-			data[0U] = m_rfFrames == 0U ? TAG_EOT : TAG_DATA;
+			data[0U] = m_rfFrames == 0U ? TAG_EOT : TAG_DATA1;
 			data[1U] = 0x00U;
 
 			if (m_duplex)
@@ -586,7 +586,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			m_display->writeDMRRSSI(m_slotNo, m_rssi);
 
 			if (!m_rfTimeout) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				if (m_duplex)
@@ -752,7 +752,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 			emb.getData(data + 2U);
 
 			if (!m_rfTimeout) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				writeNetworkRF(data, DT_VOICE, errors);
@@ -828,7 +828,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 				slotType.setDataType(DT_VOICE_LC_HEADER);
 				slotType.getData(start + 2U);
 
-				start[0U] = TAG_DATA;
+				start[0U] = TAG_DATA1;
 				start[1U] = 0x00U;
 
 				m_rfTimeoutTimer.start();
@@ -880,7 +880,7 @@ bool CDMRSlot::writeModem(unsigned char *data, unsigned int len)
 				m_rfBits += 141U;
 				m_rfFrames++;
 
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				if (m_duplex)
@@ -1088,7 +1088,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		// Convert the Data Sync to be from the BS or MS as needed
 		CSync::addDMRDataSync(data + 2U, m_duplex);
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		m_lastFrameValid = false;
@@ -1177,7 +1177,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 			slotType.setDataType(DT_VOICE_LC_HEADER);
 			slotType.getData(start + 2U);
 
-			start[0U] = TAG_DATA;
+			start[0U] = TAG_DATA1;
 			start[1U] = 0x00U;
 
 			if (m_duplex) {
@@ -1224,7 +1224,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		bptc.decode(data + 2U, payload);
 		bptc.encode(payload, data + 2U);
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		writeQueueNet(data);
@@ -1304,7 +1304,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		// Convert the Data Sync to be from the BS or MS as needed
 		CSync::addDMRDataSync(data + 2U, m_duplex);
 
-		data[0U] = m_netFrames == 0U ? TAG_EOT : TAG_DATA;
+		data[0U] = m_netFrames == 0U ? TAG_EOT : TAG_DATA1;
 		data[1U] = 0x00U;
 
 		// Put a small delay into starting transmission
@@ -1374,7 +1374,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 			slotType.setDataType(DT_VOICE_LC_HEADER);
 			slotType.getData(start + 2U);
 
-			start[0U] = TAG_DATA;
+			start[0U] = TAG_DATA1;
 			start[1U] = 0x00U;
 
 			if (m_duplex) {
@@ -1417,7 +1417,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 				m_netErrs += m_fec.regenerateDMR(data + 2U);
 			m_netBits += 141U;
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			// Convert the Audio Sync to be from the BS or MS as needed
@@ -1572,7 +1572,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		emb.setLCSS(lcss);
 		emb.getData(data + 2U);
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		// Initialise the lost packet data
@@ -1633,7 +1633,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 		// Convert the Data Sync to be from the BS or MS as needed
 		CSync::addDMRDataSync(data + 2U, m_duplex);
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		if (csbko == CSBKO_PRECCSBK && csbk.getDataContent()) {
@@ -1732,7 +1732,7 @@ void CDMRSlot::writeNetwork(const CDMRData& dmrData)
 
 		m_netFrames--;
 
-		data[0U] = m_netFrames == 0U ? TAG_EOT : TAG_DATA;
+		data[0U] = m_netFrames == 0U ? TAG_EOT : TAG_DATA1;
 		data[1U] = 0x00U;
 
 #if defined(DUMP_DMR)
diff --git a/DStarControl.cpp b/DStarControl.cpp
index 786702a1..61837dba 100644
--- a/DStarControl.cpp
+++ b/DStarControl.cpp
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2015-2019 Jonathan Naylor, G4KLX
+ *	Copyright (C) 2015-2019,2021 Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -429,7 +429,7 @@ bool CDStarControl::writeModem(unsigned char *data, unsigned int len)
 		}
 
 		return false;
-	} else if (type == TAG_DATA) {
+	} else if (type == TAG_DATA1) {
 		if (m_rfState == RS_RF_REJECTED) {
 			return false;
 		} else if (m_rfState == RS_RF_INVALID) {
@@ -779,13 +779,13 @@ void CDStarControl::writeNetwork()
 		LogMessage("D-Star, received network end of transmission from %8.8s/%4.4s to %8.8s, %.1f seconds, %u%% packet loss, BER: %.1f%%", my1, my2, your, float(m_netFrames) / 50.0F, (m_netLost * 100U) / m_netFrames, float(m_netErrs * 100U) / float(m_netBits));
 
 		writeEndNet();
-	} else if (type == TAG_DATA) {
+	} else if (type == TAG_DATA1) {
 		if (m_netState != RS_NET_AUDIO)
 			return;
 
 		unsigned char n = data[1U];
 
-		data[1U] = TAG_DATA;
+		data[1U] = TAG_DATA1;
 
 		unsigned int errors = 0U;
 		if (!m_netHeader.isDataPacket())
diff --git a/DStarDefines.h b/DStarDefines.h
index 2a3e90cd..f6ad749b 100644
--- a/DStarDefines.h
+++ b/DStarDefines.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2015,2016,2018,2019 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2015,2016,2018,2019,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -35,8 +35,8 @@ const unsigned char DSTAR_NULL_SLOW_SYNC_BYTES[] = { 0x55, 0x2D, 0x16 };
 // Note that these are already scrambled, 0x66 0x66 0x66 otherwise
 const unsigned char DSTAR_NULL_SLOW_DATA_BYTES[] = { 0x16, 0x29, 0xF5 };
 
-const unsigned char DSTAR_NULL_FRAME_SYNC_BYTES[] = { TAG_DATA, 0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x55, 0x2D, 0x16 };
-const unsigned char DSTAR_NULL_FRAME_DATA_BYTES[] = { TAG_DATA, 0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x16, 0x29, 0xF5 };
+const unsigned char DSTAR_NULL_FRAME_SYNC_BYTES[] = { TAG_DATA1, 0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x55, 0x2D, 0x16 };
+const unsigned char DSTAR_NULL_FRAME_DATA_BYTES[] = { TAG_DATA1, 0x9E, 0x8D, 0x32, 0x88, 0x26, 0x1A, 0x3F, 0x61, 0xE8, 0x16, 0x29, 0xF5 };
 
 const unsigned int  DSTAR_VOICE_FRAME_LENGTH_BYTES = 9U;
 const unsigned int  DSTAR_DATA_FRAME_LENGTH_BYTES  = 3U;
diff --git a/DStarNetwork.cpp b/DStarNetwork.cpp
index 4a978e26..2de9051b 100644
--- a/DStarNetwork.cpp
+++ b/DStarNetwork.cpp
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2009-2014,2016,2019,2020 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2009-2014,2016,2019,2020,2021 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -263,7 +263,7 @@ void CDStarNetwork::clock(unsigned int ms)
 					m_inId = 0U;
 					ctrl[1U] = TAG_EOT;
 				} else {
-					ctrl[1U] = TAG_DATA;
+					ctrl[1U] = TAG_DATA1;
 				}
 
 				ctrl[2U] = buffer[7] & 0x3FU;
@@ -299,7 +299,7 @@ unsigned int CDStarNetwork::read(unsigned char* data, unsigned int length)
 
 	switch (buffer[0U]) {
 	case TAG_HEADER:
-	case TAG_DATA:
+	case TAG_DATA1:
 	case TAG_EOT:
 		::memcpy(data, buffer, c);
 		return c;
diff --git a/Defines.h b/Defines.h
index 0381a430..58f43483 100644
--- a/Defines.h
+++ b/Defines.h
@@ -36,9 +36,10 @@ const unsigned char MODE_ERROR   = 100U;
 const unsigned char MODE_QUIT    = 110U;
 
 const unsigned char TAG_HEADER = 0x00U;
-const unsigned char TAG_DATA   = 0x01U;
-const unsigned char TAG_LOST   = 0x02U;
-const unsigned char TAG_EOT    = 0x03U;
+const unsigned char TAG_DATA1  = 0x01U;
+const unsigned char TAG_DATA2  = 0x02U;
+const unsigned char TAG_LOST   = 0x03U;
+const unsigned char TAG_EOT    = 0x04U;
 
 const unsigned int  DSTAR_MODEM_DATA_LEN = 220U;
 
diff --git a/FMControl.cpp b/FMControl.cpp
index 7f1ff073..1708c61a 100644
--- a/FMControl.cpp
+++ b/FMControl.cpp
@@ -81,7 +81,7 @@ bool CFMControl::writeModem(const unsigned char* data, unsigned int length)
     if (data[0U] == TAG_EOT)
         return m_network->writeEOT();
 
-    if (data[0U] != TAG_DATA)
+    if (data[0U] != TAG_DATA1)
         return false;
 
     m_incomingRFAudio.addData(data + 1U, length - 1U);
diff --git a/M17Control.cpp b/M17Control.cpp
index aaf2342c..653413df 100644
--- a/M17Control.cpp
+++ b/M17Control.cpp
@@ -135,6 +135,12 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		return false;
 	}
 
+	// Ignore packet data
+	if (type == TAG_DATA2) {
+		m_rfState = RS_RF_LISTENING;
+		return false;
+	}
+
 	// Have we got RSSI bytes on the end?
 	if (len == (M17_FRAME_LENGTH_BYTES + 4U)) {
 		uint16_t raw = 0U;
@@ -200,12 +206,12 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		}
 	}
 
-	if (m_rfState == RS_RF_LISTENING && data[0U] == TAG_DATA) {
+	if (m_rfState == RS_RF_LISTENING && data[0U] == TAG_DATA1) {
 		m_rfState = RS_RF_LATE_ENTRY;
 		m_rfLSF.reset();
 	}
 
-	if (m_rfState == RS_RF_LATE_ENTRY && data[0U] == TAG_DATA) {
+	if (m_rfState == RS_RF_LATE_ENTRY && data[0U] == TAG_DATA1) {
 		bool valid1, valid2, valid3, valid4;
 		unsigned int lich1 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 0U, valid1);
 		unsigned int lich2 = CGolay24128::decode24128(data + 2U + M17_SYNC_LENGTH_BYTES + 3U, valid2);
@@ -247,7 +253,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 		}
 	}
 
-	if (m_rfState == RS_RF_AUDIO && data[0U] == TAG_DATA) {
+	if (m_rfState == RS_RF_AUDIO && data[0U] == TAG_DATA1) {
 #if defined(DUMP_M17)
 		writeFile(data + 2U);
 #endif
@@ -271,7 +277,7 @@ bool CM17Control::writeModem(unsigned char* data, unsigned int len)
 
 		unsigned char rfData[2U + M17_FRAME_LENGTH_BYTES];
 
-		rfData[0U] = TAG_DATA;
+		rfData[0U] = TAG_DATA1;
 		rfData[1U] = 0x00U;
 
 		// Generate the sync
@@ -487,7 +493,7 @@ void CM17Control::writeNetwork()
 	if (m_netState == RS_NET_AUDIO) {
 		unsigned char data[M17_FRAME_LENGTH_BYTES + 2U];
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		// Generate the sync
@@ -547,6 +553,10 @@ void CM17Control::writeNetwork()
 
 bool CM17Control::processRFHeader(bool lateEntry)
 {
+	unsigned char packetStream = m_rfLSF.getPacketStream();
+	if (packetStream == M17_PACKET_TYPE)
+		return false;
+
 	unsigned char can = m_rfLSF.getCAN();
 	if (can != m_can)
 		return false;
diff --git a/Modem.cpp b/Modem.cpp
index 795302b0..1a33935c 100644
--- a/Modem.cpp
+++ b/Modem.cpp
@@ -468,7 +468,7 @@ void CModem::clock(unsigned int ms)
 					unsigned char data = m_length - m_offset + 1U;
 					m_rxDStarData.addData(&data, 1U);
 
-					data = TAG_DATA;
+					data = TAG_DATA1;
 					m_rxDStarData.addData(&data, 1U);
 
 					m_rxDStarData.addData(m_buffer + m_offset, m_length - m_offset);
@@ -509,7 +509,7 @@ void CModem::clock(unsigned int ms)
 					if (m_buffer[3U] == (DMR_SYNC_DATA | DT_TERMINATOR_WITH_LC))
 						data = TAG_EOT;
 					else
-						data = TAG_DATA;
+						data = TAG_DATA1;
 					m_rxDMRData1.addData(&data, 1U);
 
 					m_rxDMRData1.addData(m_buffer + m_offset, m_length - m_offset);
@@ -526,7 +526,7 @@ void CModem::clock(unsigned int ms)
 					if (m_buffer[3U] == (DMR_SYNC_DATA | DT_TERMINATOR_WITH_LC))
 						data = TAG_EOT;
 					else
-						data = TAG_DATA;
+						data = TAG_DATA1;
 					m_rxDMRData2.addData(&data, 1U);
 
 					m_rxDMRData2.addData(m_buffer + m_offset, m_length - m_offset);
@@ -564,7 +564,7 @@ void CModem::clock(unsigned int ms)
 					unsigned char data = m_length - m_offset + 1U;
 					m_rxYSFData.addData(&data, 1U);
 
-					data = TAG_DATA;
+					data = TAG_DATA1;
 					m_rxYSFData.addData(&data, 1U);
 
 					m_rxYSFData.addData(m_buffer + m_offset, m_length - m_offset);
@@ -604,7 +604,7 @@ void CModem::clock(unsigned int ms)
 				unsigned char data = m_length - m_offset + 1U;
 				m_rxP25Data.addData(&data, 1U);
 
-				data = TAG_DATA;
+				data = TAG_DATA1;
 				m_rxP25Data.addData(&data, 1U);
 
 				m_rxP25Data.addData(m_buffer + m_offset, m_length - m_offset);
@@ -630,7 +630,7 @@ void CModem::clock(unsigned int ms)
 				unsigned char data = m_length - m_offset + 1U;
 				m_rxNXDNData.addData(&data, 1U);
 
-				data = TAG_DATA;
+				data = TAG_DATA1;
 				m_rxNXDNData.addData(&data, 1U);
 
 				m_rxNXDNData.addData(m_buffer + m_offset, m_length - m_offset);
@@ -670,7 +670,7 @@ void CModem::clock(unsigned int ms)
 				unsigned char data = m_length - 2U;
 				m_rxM17Data.addData(&data, 1U);
 
-				data = TAG_DATA;
+				data = TAG_DATA1;
 				m_rxM17Data.addData(&data, 1U);
 
 				m_rxM17Data.addData(m_buffer + 3U, m_length - 3U);
@@ -684,7 +684,7 @@ void CModem::clock(unsigned int ms)
 				unsigned char data = m_length - 2U;
 				m_rxM17Data.addData(&data, 1U);
 
-				data = TAG_DATA;
+				data = TAG_DATA2;
 				m_rxM17Data.addData(&data, 1U);
 
 				m_rxM17Data.addData(m_buffer + 3U, m_length - 3U);
@@ -710,7 +710,7 @@ void CModem::clock(unsigned int ms)
 				unsigned int data1 = m_length - m_offset + 1U;
 				m_rxFMData.addData((unsigned char*)&data1, sizeof(unsigned int));
 
-				unsigned char data2 = TAG_DATA;
+				unsigned char data2 = TAG_DATA1;
 				m_rxFMData.addData(&data2, 1U);
 
 				m_rxFMData.addData(m_buffer + m_offset, m_length - m_offset);
@@ -1322,7 +1322,7 @@ bool CModem::writeDStarData(const unsigned char* data, unsigned int length)
 		case TAG_HEADER:
 			buffer[2U] = MMDVM_DSTAR_HEADER;
 			break;
-		case TAG_DATA:
+		case TAG_DATA1:
 			buffer[2U] = MMDVM_DSTAR_DATA;
 			break;
 		case TAG_EOT:
@@ -1361,7 +1361,7 @@ bool CModem::writeDMRData1(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[40U];
@@ -1384,7 +1384,7 @@ bool CModem::writeDMRData2(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[40U];
@@ -1414,7 +1414,7 @@ bool CModem::writeYSFData(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[130U];
@@ -1444,7 +1444,7 @@ bool CModem::writeP25Data(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_HEADER && data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_HEADER && data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[250U];
@@ -1474,7 +1474,7 @@ bool CModem::writeNXDNData(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[130U];
@@ -1504,7 +1504,7 @@ bool CModem::writeM17Data(const unsigned char* data, unsigned int length)
 	assert(data != NULL);
 	assert(length > 0U);
 
-	if (data[0U] != TAG_HEADER && data[0U] != TAG_DATA && data[0U] != TAG_EOT)
+	if (data[0U] != TAG_HEADER && data[0U] != TAG_DATA1 && data[0U] != TAG_EOT)
 		return false;
 
 	unsigned char buffer[130U];
@@ -1823,7 +1823,7 @@ bool CModem::writePOCSAGInfo(unsigned int ric, const std::string& message)
 	unsigned char buffer[250U];
 
 	buffer[0U] = MMDVM_FRAME_START;
-	buffer[1U] = length + 11U;
+	buffer[1U] = (unsigned char)length + 11U;
 	buffer[2U] = MMDVM_QSO_INFO;
 
 	buffer[3U] = MODE_POCSAG;
@@ -1832,7 +1832,7 @@ bool CModem::writePOCSAGInfo(unsigned int ric, const std::string& message)
 
 	::memcpy(buffer + 11U, message.c_str(), length);
 
-	int ret = m_port->write(buffer, length + 11U);
+	int ret = m_port->write(buffer, (unsigned int)length + 11U);
 
 	return ret != int(length + 11U);
 }
@@ -1846,14 +1846,14 @@ bool CModem::writeIPInfo(const std::string& address)
 	unsigned char buffer[25U];
 
 	buffer[0U] = MMDVM_FRAME_START;
-	buffer[1U] = length + 4U;
+	buffer[1U] = (unsigned char)length + 4U;
 	buffer[2U] = MMDVM_QSO_INFO;
 
 	buffer[3U] = 250U;
 
 	::memcpy(buffer + 4U, address.c_str(), length);
 
-	int ret = m_port->write(buffer, length + 4U);
+	int ret = m_port->write(buffer, (unsigned int)length + 4U);
 
 	return ret != int(length + 4U);
 }
@@ -2485,7 +2485,7 @@ bool CModem::sendCWId(const std::string& callsign)
 {
 	assert(m_port != NULL);
 
-	unsigned int length = callsign.length();
+	unsigned int length = (unsigned int)callsign.length();
 	if (length > 200U)
 		length = 200U;
 
@@ -2631,7 +2631,7 @@ bool CModem::setFMCallsignParams()
 	assert(m_port != NULL);
 
 	unsigned char buffer[80U];
-	unsigned char len = 10U + m_fmCallsign.size();
+	unsigned char len = 10U + (unsigned char)m_fmCallsign.size();
 
 	buffer[0U] = MMDVM_FRAME_START;
 	buffer[1U] = len;
@@ -2692,7 +2692,7 @@ bool CModem::setFMAckParams()
 	assert(m_port != NULL);
 
 	unsigned char buffer[80U];
-	unsigned char len = 8U + m_fmRfAck.size();
+	unsigned char len = 8U + (unsigned char)m_fmRfAck.size();
 
 	buffer[0U] = MMDVM_FRAME_START;
 	buffer[1U] = len;
@@ -2811,7 +2811,7 @@ bool CModem::setFMExtParams()
 	assert(m_port != NULL);
 
 	unsigned char buffer[80U];
-	unsigned char len = 7U + m_fmExtAck.size();
+	unsigned char len = 7U + (unsigned char)m_fmExtAck.size();
 
 	buffer[0U] = MMDVM_FRAME_START;
 	buffer[1U] = len;
diff --git a/NXDNControl.cpp b/NXDNControl.cpp
index 119fad65..d040ca78 100644
--- a/NXDNControl.cpp
+++ b/NXDNControl.cpp
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2015-2020 Jonathan Naylor, G4KLX
+ *	Copyright (C) 2015-2021 Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -223,7 +223,7 @@ bool CNXDNControl::processVoice(unsigned char usc, unsigned char option, unsigne
 
 		m_rfLayer3 = layer3;
 
-		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA;
+		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA1;
 		data[1U] = 0x00U;
 
 		CSync::addNXDNSync(data + 2U);
@@ -401,7 +401,7 @@ bool CNXDNControl::processVoice(unsigned char usc, unsigned char option, unsigne
 			// Create a dummy start message
 			unsigned char start[NXDN_FRAME_LENGTH_BYTES + 2U];
 
-			start[0U] = TAG_DATA;
+			start[0U] = TAG_DATA1;
 			start[1U] = 0x00U;
 
 			// Generate the sync
@@ -539,7 +539,7 @@ bool CNXDNControl::processVoice(unsigned char usc, unsigned char option, unsigne
 			facch12.getRaw(netData + 5U + 14U);
 		}
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		scrambler(data + 2U);
@@ -638,12 +638,12 @@ bool CNXDNControl::processData(unsigned char option, unsigned char *data)
 
 	if (validUDCH) {
 		type = layer3.getMessageType();
-		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA;
+		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA1;
 
 		udch.setRAN(m_ran);
 		udch.encode(data + 2U);
 	} else {
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 	}
 
@@ -785,7 +785,7 @@ void CNXDNControl::writeNetwork()
 		}
 
 		if (m_netState == RS_NET_DATA) {
-			data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA;
+			data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA1;
 			data[1U] = 0x00U;
 
 			CNXDNUDCH udch;
@@ -826,7 +826,7 @@ void CNXDNControl::writeNetwork()
 		facch.encode(data + 2U, NXDN_FSW_LENGTH_BITS + NXDN_LICH_LENGTH_BITS + NXDN_SACCH_LENGTH_BITS);
 		facch.encode(data + 2U, NXDN_FSW_LENGTH_BITS + NXDN_LICH_LENGTH_BITS + NXDN_SACCH_LENGTH_BITS + NXDN_FACCH1_LENGTH_BITS);
 
-		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA;
+		data[0U] = type == NXDN_MESSAGE_TYPE_TX_REL ? TAG_EOT : TAG_DATA1;
 		data[1U] = 0x00U;
 
 		scrambler(data + 2U);
@@ -907,7 +907,7 @@ void CNXDNControl::writeNetwork()
 			// Create a dummy start message
 			unsigned char start[NXDN_FRAME_LENGTH_BYTES + 2U];
 
-			start[0U] = TAG_DATA;
+			start[0U] = TAG_DATA1;
 			start[1U] = 0x00U;
 
 			// Generate the sync
@@ -942,7 +942,7 @@ void CNXDNControl::writeNetwork()
 
 		m_netFrames++;
 
-		data[0U] = TAG_DATA;
+		data[0U] = TAG_DATA1;
 		data[1U] = 0x00U;
 
 		CNXDNSACCH sacch;
diff --git a/P25Control.cpp b/P25Control.cpp
index b9825f01..3e382eaf 100644
--- a/P25Control.cpp
+++ b/P25Control.cpp
@@ -1,5 +1,5 @@
 /*
-*   Copyright (C) 2016-2019 by Jonathan Naylor G4KLX
+*   Copyright (C) 2016-2019,2021 by Jonathan Naylor G4KLX
 *   Copyright (C) 2018 by Bryan Biedenkapp <gatekeep@gmail.com>
 *
 *   This program is free software; you can redistribute it and/or modify
@@ -303,7 +303,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 			::memcpy(m_rfLDU, data + 2U, P25_LDU_FRAME_LENGTH_BYTES);
 
 			if (m_duplex) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 				writeQueueRF(data, P25_LDU_FRAME_LENGTH_BYTES + 2U);
 			}
@@ -349,7 +349,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 			::memcpy(m_rfLDU, data + 2U, P25_LDU_FRAME_LENGTH_BYTES);
 
 			if (m_duplex) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 				writeQueueRF(data, P25_LDU_FRAME_LENGTH_BYTES + 2U);
 			}
@@ -399,7 +399,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 			setBusyBits(data + 2U, P25_SS0_START, true, true);
 
 			if (m_duplex) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				writeQueueRF(data, P25_TSDU_FRAME_LENGTH_BYTES + 2U);
@@ -425,7 +425,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 			setBusyBits(data + 2U, P25_SS0_START, true, true);
 
 			if (m_duplex) {
-				data[0U] = TAG_DATA;
+				data[0U] = TAG_DATA1;
 				data[1U] = 0x00U;
 
 				writeQueueRF(data, P25_TSDU_FRAME_LENGTH_BYTES + 2U);
@@ -569,7 +569,7 @@ bool CP25Control::writeModem(unsigned char* data, unsigned int len)
 				addBusyBits(pdu + 2U, newBitLength, false, true);
 
 				if (m_duplex) {
-					pdu[0U] = TAG_DATA;
+					pdu[0U] = TAG_DATA1;
 					pdu[1U] = 0x00U;
 					writeQueueRF(pdu, newByteLength + 2U);
 				}
@@ -1010,7 +1010,7 @@ void CP25Control::createNetLDU1()
 	unsigned char buffer[P25_LDU_FRAME_LENGTH_BYTES + 2U];
 	::memset(buffer, 0x00U, P25_LDU_FRAME_LENGTH_BYTES + 2U);
 
-	buffer[0U] = TAG_DATA;
+	buffer[0U] = TAG_DATA1;
 	buffer[1U] = 0x00U;
 
 	// Add the sync
@@ -1058,7 +1058,7 @@ void CP25Control::createNetLDU2()
 	unsigned char buffer[P25_LDU_FRAME_LENGTH_BYTES + 2U];
 	::memset(buffer, 0x00U, P25_LDU_FRAME_LENGTH_BYTES + 2U);
 
-	buffer[0U] = TAG_DATA;
+	buffer[0U] = TAG_DATA1;
 	buffer[1U] = 0x00U;
 
 	// Add the sync
diff --git a/Version.h b/Version.h
index 36c3a746..7dbf25da 100644
--- a/Version.h
+++ b/Version.h
@@ -19,6 +19,6 @@
 #if !defined(VERSION_H)
 #define	VERSION_H
 
-const char* VERSION = "20210328";
+const char* VERSION = "20210329";
 
 #endif
diff --git a/YSFControl.cpp b/YSFControl.cpp
index 88551600..efb2213c 100644
--- a/YSFControl.cpp
+++ b/YSFControl.cpp
@@ -1,5 +1,5 @@
 /*
- *	Copyright (C) 2015-2020 Jonathan Naylor, G4KLX
+ *	Copyright (C) 2015-2021 Jonathan Naylor, G4KLX
  *
  *	This program is free software; you can redistribute it and/or modify
  *	it under the terms of the GNU General Public License as published by
@@ -265,7 +265,7 @@ bool CYSFControl::processVWData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -358,7 +358,7 @@ bool CYSFControl::processVWData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -434,7 +434,7 @@ bool CYSFControl::processDNData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -540,7 +540,7 @@ bool CYSFControl::processDNData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -636,7 +636,7 @@ bool CYSFControl::processDNData(bool valid, unsigned char *data)
 			CYSFPayload payload;
 			payload.writeHeader(buffer + 2U, csd1, csd2);
 
-			buffer[0U] = TAG_DATA;
+			buffer[0U] = TAG_DATA1;
 			buffer[1U] = 0x00U;
 
 			writeNetwork(buffer, m_rfFrames % 128U);
@@ -660,7 +660,7 @@ bool CYSFControl::processDNData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -733,7 +733,7 @@ bool CYSFControl::processFRData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -814,7 +814,7 @@ bool CYSFControl::processFRData(bool valid, unsigned char *data)
 
 			fich.encode(data + 2U);
 
-			data[0U] = TAG_DATA;
+			data[0U] = TAG_DATA1;
 			data[1U] = 0x00U;
 
 			writeNetwork(data, m_rfFrames % 128U);
@@ -949,7 +949,7 @@ void CYSFControl::writeNetwork()
 			return;
 	}
 
-	data[33U] = end ? TAG_EOT : TAG_DATA;
+	data[33U] = end ? TAG_EOT : TAG_DATA1;
 	data[34U] = 0x00U;
 
 	if (valid) {