Not sure if anyone can give me any pointers to diagnose the following issue:

I recently bought a Tannoy BaseStation One TV soundbar. While watching a
film, the audio will cut out for maybe half a second every 20 minutes or
so. Possibly relevant detail:

The BaseStation is connected directly to the TV with an optical cable;
The cut in sound never happens in the same place twice;
It also happens when optically connected directly to the Blu-ray player;
The BaseStation has replaced an AV amp, which was also optically linked
to the TV, and had no issues.

Any ideas please?

--
Cheers, Rob