Everything else appears to be working fine, and the fan in particular - which I thought could be a likely suspect - is nice and quiet in operation. I'm thinking it'd down to a poor quality transformer.

On Friday, 29 November 2019 07:51:24 UTC, Brian Gaff (Sofa 2) wrote:
It is
likely that something in the power supply circuit has put a short on the
secondary, or the transformer merely has broken down with shorted turns.
I'd have thought if there had been a fan or other bad component then you
might actually see it or hear it, ie lack of sound if its failed, so short
of trying to get a transformer and replacing the old board