diff --git a/NmraDcc.cpp b/NmraDcc.cpp
index 05626d8..e01193d 100644
--- a/NmraDcc.cpp
+++ b/NmraDcc.cpp
@@ -1101,7 +1101,8 @@ void execDccProcessor( DCC_MSG * pDccMsg )
     {
       resetServiceModeTimer( 1 ) ;
 
-      if( memcmp( pDccMsg, &DccProcState.LastMsg, sizeof( DCC_MSG ) ) )
+	//Only check the DCC Packet "Size" and "Data" fields and ignore the "PreambleBits" as they can be different to the previous packet
+      if(pDccMsg->Size != DccProcState.LastMsg.Size || memcmp( pDccMsg->Data, &DccProcState.LastMsg.Data, pDccMsg->Size ) != 0 )	      
       {
         DccProcState.DuplicateCount = 0 ;
         memcpy( &DccProcState.LastMsg, pDccMsg, sizeof( DCC_MSG ) ) ;