Hey everyone, I have a vintage JMP Super Lead 100 and it started making a sort of loud static-like sound when I play. It doesn’t have any problem if I don’t play, and the problem seems to increase as I increase the treble/presence. I have tried the head with another cab, it has the same problem. I took it to two different techs, they couldn’t fix it. I changed the preamp and power amp tubes, I cleaned the tubes sockets, nothing seems to work and I’m getting pretty desperate because it really is a killer amp and I don’t have any ideas anymore. Can somebody help me? By the way, is it possible to send a video or an audio file so that you can see or at least listen to the sound it makes? I'm don't seem to be able to.