On Fri, 18 Mar 2011 14:03:22 +0000, Jules Richardson wrote:
As an update, I tried some IPA, and that gave a huge improvement - in
fact, it was perfect for a few days. As of this morning I'm suddenly
getting signal drop-out on the left channel, but I suspect this isn't
related to switch/pot contacts.

Oh, and the other channel followed it some 30 mins or so later. Strange
that they didn't fail at the same time. It might be an age-related
component failure and it's just coincidence that both channels died
within a narrow space of time - or a single component failure has had
some kind of knock-on effect that's killed something in both channels
(and it took one side longer to go bad than the other).

I might get a chance later today to do some more in-depth digging.
Ignoring the tuner stages, I don't think this thing is particularly
complex, so it shouldn't take long to trace a schematic out.

cheers

Jules