diff --git a/DMRDataHeader.cpp b/DMRDataHeader.cpp
index ef0922d..246ba4e 100644
--- a/DMRDataHeader.cpp
+++ b/DMRDataHeader.cpp
@@ -29,6 +29,8 @@
 #include <cassert>
 #include <cstring>
 
+const unsigned char UDTF_NMEA = 0x05U;
+
 CDMRDataHeader::CDMRDataHeader() :
 m_data(NULL),
 m_GI(false),
@@ -78,13 +80,13 @@ bool CDMRDataHeader::put(const unsigned char* bytes)
 
 	switch (dpf) {
 	case DPF_UNCONFIRMED_DATA:
-		CUtils::dump(1U, "Unconfirmed Data Header", m_data, 12U);
+		CUtils::dump(1U, "DMR, Unconfirmed Data Header", m_data, 12U);
 		m_F = (m_data[8U] & 0x80U) == 0x80U;
 		m_blocks = m_data[8U] & 0x7FU;
 		break;
 
 	case DPF_CONFIRMED_DATA:
-		CUtils::dump(1U, "Confirmed Data Header", m_data, 12U);
+		CUtils::dump(1U, "DMR, Confirmed Data Header", m_data, 12U);
 		m_F = (m_data[8U] & 0x80U) == 0x80U;
 		m_blocks = m_data[8U] & 0x7FU;
 		m_S = (m_data[9U] & 0x80U) == 0x80U;
@@ -92,38 +94,46 @@ bool CDMRDataHeader::put(const unsigned char* bytes)
 		break;
 
 	case DPF_RESPONSE:
-		CUtils::dump(1U, "Response Data Header", m_data, 12U);
+		CUtils::dump(1U, "DMR, Response Data Header", m_data, 12U);
 		m_blocks = m_data[8U] & 0x7FU;
 		break;
 
 	case DPF_PROPRIETARY:
-		CUtils::dump(1U, "Proprietary Data Header", m_data, 12U);
+		CUtils::dump(1U, "DMR, Proprietary Data Header", m_data, 12U);
 		break;
 
 	case DPF_DEFINED_RAW:
-		CUtils::dump(1U, "Raw or Status/Precoded Short Data Header", m_data, 12U);
+		CUtils::dump(1U, "DMR, Raw or Status/Precoded Short Data Header", m_data, 12U);
 		m_blocks = (m_data[0U] & 0x30U) + (m_data[1U] & 0x0FU);
 		m_F = (m_data[8U] & 0x01U) == 0x01U;
 		m_S = (m_data[8U] & 0x02U) == 0x02U;
 		break;
 
 	case DPF_DEFINED_SHORT:
-		CUtils::dump(1U, "Defined Short Data Header", m_data, 12U);
+		CUtils::dump(1U, "DMR, Defined Short Data Header", m_data, 12U);
 		m_blocks = (m_data[0U] & 0x30U) + (m_data[1U] & 0x0FU);
 		m_F = (m_data[8U] & 0x01U) == 0x01U;
 		m_S = (m_data[8U] & 0x02U) == 0x02U;
 		break;
 
 	case DPF_UDT:
-		CUtils::dump(1U, "Unified Data Transport Header", m_data, 12U);
+		CUtils::dump(1U, "DMR, Unified Data Transport Header", m_data, 12U);
 		m_blocks = m_data[8U] & 0x03U;
 		break;
 
 	default:
-		CUtils::dump("Unknown Data Header", m_data, 12U);
+		CUtils::dump("DMR, Unknown Data Header", m_data, 12U);
 		break;
 	}
 
+	if (dpf == DPF_UDT && m_blocks == 0U) {
+		unsigned char format = m_data[1U] & 0x0FU;
+		if (format == UDTF_NMEA) {
+			LogDebug("DMR, fixing broken Tytera MD-390 GPS data block count");
+			m_blocks = 2U;
+		}
+	}
+
 	return true;
 }