Thanks for the responses

Matt

The laptop soundcard is a Conexant Smart Audio HD and I also use an external USB SoundBlaster SBX-Fi-Go-Pro, I have no idea what the card was in my previous laptop. In every case the blip was the same so I wonder why it could be due to the particular card/driver.

Rharv

Your description "sounds like the buffer unloading" fits the symptoms and I have occasionally heard a blip at the beginning of a song. However I cannot reproduce it at the beginning.
The blip at the end happens every time I play the same song however I will recheck if I hear another starting blip.

Perhaps I should mention that I nearly always use a "manual" song ending e.g. A... to hold all tracks, followed by B. to stop all tracks. I have tried using a two bar ending generated by BIAB but still get the blip.

BTW I have created hundreds of songs with at least one RT and every single one blips!!

Tony