Hi Allan,
It may be sound lag causing this. Check in Surveyor, open route to edit it, but don't save it afterwards, and find out what the track and turnouts are.
What I mean by lag is the sounds aren't keeping up with the video playback in driver. It's like the audio is out of synch when you watch movies or news broadcasts. The mouths of the actors move first, then the audio comes through a split second later.
This can be caused by a number of things including a fragmented hard drive, which affects performance overall and can cause stutters as the database is read while Trainz is running.
John