(yeah i know these amps have alot of problems) haha So a while ago my Ampeg svt4pro developed this sort of rattle sound when i would play a note. It kind of sounds like a blown speaker, but does it no matter what cab I play through. Today I replaced the 3 12ax7's and it still does it. To be honest, i'm pretty clueless when it comes to Tech stuff, so I have no idea what it could be. Any ideas or help would be Greatly appreciated!