Looking for some insight that might help me save my amp. I bought a first gen way back, and it sat unused for decades. Looking to resurrect, I pulled it out of storage. No sound :(. Although there was a loud hum from the speaker, the master volume knob did nothing, it was as if it was stuck at max volume but there was no guitar tone. No scratches from the knob, nothing. I could change channels and such but it wasn't really playable. I figured there was an issue with the master volume pot. I pulled it apart, and used contact cleaner on all the pots, with zero effect. Then I learned it's not a pot at all, but an electronic switch. I read on the forums here about resetting it to factory defaults by turning it on while holding all four channel buttons down. I did that and it appears to have reset it successfully. There is no speaker hum until I let the buttons go, so I'm starting to think it's a software issue. (I found the firmware test - holding Channel C button down while start it up, I have firmware 1.5).
So in a last ditch effort, I resurrected the floorboard, plugged it in and it appears to be working great. As soon as I put the volume pedal down the amp is at full volume. I can change the volume with the floor board pedal, but I can't cut the master volume to avoid the hum.
I'm hoping someone has a trick to help get the amp back to usable. Otherwise I guess I better go amp shopping.