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.

Jonathan, April 2009

Yes!! Definitely the pots - probably been in a damp place a while or just lack of use, even over use. Either way Peccavi is correct - get some spray servisol or similar switch cleaner and give the backs or any place on each pot (Control) where you can access the slider and you should find them to be good as new

Garythebloke, August 2010

That's a rare skill - looking at vacuum tubes and diagnosing faults from their appearance (heater faults notwithstanding) - hats off to you...

Peccavi, May 2009

Unless you have electronic repair knowledge I think you should get your amp to a service technician. Solid state amps are quite difficult to diagnose, you can't just look at it and determine the problem (tube amps are different, lots of times you can just look at the tubes and see that there is something wrong).

Nick Steel, May 2009

I don't know the actual cause of your problem but as a retired service engineer the first thing I would suspect is dirty pots - go to an electrical components shop and get some cleaner spray - I think the stuff we used was called Servisol - quick squirt in the control potentiometers and a few rapid turns was often enough to restore a dodgy control. It's quick and relatively easy. If it doesn't work you will not have lost much...

http://www.rocketradio.co.uk/ekmps/shops/rocketradio/images/servisol_super_10.jpg

Peccavi, April 2009