Guitar amp sudden spikes in volume?

I have a crate RFX120 solid state combo that, after a good 30 minutes to an hour of consistent playing, begins to randomly spike in volume to what even seems like a volume not achievable by nob adjustment. It started about a year after I got it and I've owned it for about 2 1/2. Recently I went a couple of months without playing it and after 3-4 band practices the problem started up again.

What the f man? I'm sure it has something to do with the circuitry but I wouldn't know the specifics. It happens in every setting - "clean, rhythm, and solo" (clean, distorted tone, fuzz).

I also have problems with the reverb/other effects, for whenever I adjust the nobs they either don't register the labeled effect at all or take 3-4 nob rotations to start working.

Whenever I play my amp through the direct insert (not through the board) and use separate pedals the problem does not occur.

If you can help I'll send you a sandwich or something similarly awesome.