My friend has a peavey bravo 112 that he uses for bass and guitar. He put an actual bass speaker in it so at least he won't shred the speaker. He's been using it for about a year but recently it started occasionally sounding really fizzy and stuff when he plays it. It's not cords, jacks, pickups or any of that. I've used my various guitars and my other friends bass on it.

It sounds almost like its on the distortion channel, but it sounds really fizzy and weak no matter where the volume is, but if you jiggle the volume knob sometimes it'll kick in and sound crystal clear again. It usually sounds fine, just occasionally when we first start playing.

Any ideas?
Winner of the 2011 Virginia Guitar Festival

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