Humming amps :(

["Tony Butler" <lists@xxxxxxx>]

Hi kids,

Was on hols recently whilst workmen finished off kitchen.
When I came back, one of my multi room amp (a Parasound Zamp) was
humming (well okay, the speakers were humming, but the source is the
amp) when switched on.
Dunno if workmen had tried to play with kit and had amps on but knekt
system feeding it off, or if the build up of heat in the cupboard
knobbled it....
Anyway, luckily I had a "spare", recently returned from holidays
in
Phils house, so I swapped em out and all was well again.

HOWEVER, yesterday SWMBO noticed no sound in the dining room and on
investigation, the feed to that zone from the Knekt Intersekt had become
disconnected when I was fiddling about in N0 recently.  So SWMBO had the
zone on with nowt feeding to it.
Plugged it all back in this morning and....this amp is humming now.....
Again, has been hot recently so maybe.....but definitely amp has been
on, volume up, no signal feeding it - so I'm wondering if this has
buggered anything?
After all, amps have been in same cupboard, on 24/7 for 3 yrs now
without incident.

Music does still play thru amp, but with it on and source feed off,
loud(ish) annoying hum issues forth :(

Can anyone suggest something simple it might be that a man of limited
skillz such as myself might try?  Or alternatively, do you know of
somewhere Croydon-ish that repairs amps without charging an arm and a
leg?

Cheers,


Tony.