I was given an Old Peavey TNT 100 amp and no matter what bass or cord I use, and no matter what the volume or gain is set at, I get a fuzz tone. I plugged a external cabinet into the speaker jack and get the same tone, so I know its not the speaker. I tried 3 different cords, and both passive and active basses, so I know it is definitely the amp. Other amps plugged in to the same outlet dont have it either, so its not the electricity. There are no tubes, so thats not an issue either. Any other ideas?