In article ,
Trevor Wilson wrote:
Snag is this squawk happens immediately at switch off. So the relay
would have to operate extremely quickly.

**Phil's idea is a good one. I used exactly that solution a short time
back with a Sony integrated amp. The preamp section was going unstable
at switch-off. The job was rapidly becoming unviable, so, after
consultation with the client, he agreed that a fast operating relay
would be acceptable. I used it to short the output of the preamp to
earth at switch-off. Perfect solution. Not ideal, but it does work well.

But not really an answer to my question, thanks.

It's an fairly obvious 'cure' although might well not be perfect in
practice.

--
*ONE NICE THING ABOUT EGOTISTS: THEY DON'T TALK ABOUT OTHER PEOPLE.

Dave Plowman London SW
To e-mail, change noise into sound.