I know that the best advice is to take to a professional amp service centre, but I'm wondering if there are any tips any one has that may save me the cash.. I've had some experience doing basic electrical repairs in theatrical equipment and a range of solid state amps, and work with a bunch of electricians and repair techs, so between us I'm sure we could sort out wiring issues..

I bought a use Peavey Classic 30, just arrived today. Plugged it in at work and it was fine, plugged it in at home and it tripped the RCD as soon as the plug went into the wall.. That suggests and earth leak somewhere, but I've had a quick look inside and haven't been able to identify any obvious short circuits.

I wonder if any one can suggest a part of the circuit that's more likely to have caused this fault than another? A friend of mine had it for me for a few weeks before I was able to pick it up, and ran it without issue. I'm having it put through a PAT machine tomorrow at work to try and shed some light on it, but in the mean time... Any bright ideas?
PRS SE Chris Robertson
PRS SE Angelus Custom
Yamaha SF1000 (Both of 'em)

Laney L20H Lionheart
Marshall 1936 w/ Eminence

Rather large pedalboard..