I have a crate gt 80. The volume keeps cutting in and out. I have replaced the main input Jack cleaned the pots really good and replaced two Zener diodes IN5353B and the problem still exists. From what I have read up on these amps this is a common problem. It occurs on both solid state and tube settings. I have read that putting a cable from line in and line out on the back of the amp fixes the problem. So far I have tried that and it seems to work well. Does anybody know what part needs to be replaced that would cause the amp to cut in and out. Thanks. Mike