So, because people here have been so good to me, I thought I'd pose another riddle. I have a silver stripe era peavey studio pro 112. It mostly sounds great, but I have a small problem. In my lessons studio it seems to pick up a lot of interference. My previous amps in that space, a crate gx40c and g60 picked up some, but not this badly.

There's some 60 cycle hum and a bit of noise from fluorescent lighting, but that's not the worst of it. My cell phone (the fruit brand) drives it nuts. Turning up the reverb is like turning up the hum. Can I add shielding to the enclosure? Maybe shield the reverb cables or tank as well? What are the risks? Thermal issues? Microphonics?

Also, for bonus points, a previous owner removed the handle on top. Something else leaked through the hole and so now a jumper wire and a transistor(?) next to the main heatsink are corroded. They seem to work, and if sometimes the dirt channel doesn't work, a swift blow to the chassis brings it back in line. I'm inclined to leave it alone. What are the chances that's contributing?

So I picked up a crate g60 as part of a CL deal, looking for a good SS amp to serve as a small PA, gig amp and lesson studio knock around.

At first it hummed like crazy, but that was fixed by simply removing the power stage and cleaning the chassis a bit (it's crazy rusted with bug bits inside).

The reverb is wimpy and the distortion channel lights up, but has no output.
The most sophisticated diagnostic gear I have is an analog meter. Should I even mess with this thing, or toss it back into the CL pit?