Ey guys a while back I bought a second hand Peavey bandit 112 2005 red strip. Its a great amp when its working but it has a recurring problem that seems to have stuck. The main issue is on the lead channel, its gets very buzzy and compresses like hell, when playing at louder volumes it swells and has barely any sustain, it also doesnt sound if you play it lightly. Its becomes pretty much unplayable playing at high volumes. Took it in for repairs and the dude couldn't find out what the problem was. Any suggestions? Was thinking of trying to run an external speaker, would a standard monitor do the trick for testing?