Posted about this on a guitar forum, but it's a slow forum and I need to get some possible answers by tomorrow. The amp is a Fender pro 185, all stock. The amp powers up and the foot switch works as well as all of the lights. But no sound goes to the speakers. Not even the "pop" that tells you it's on. The amp is solid state and from the late '80's. Any ideas on what could be wrong and how to diagnose it? I can solder and follow schematics. And finding replacement parts shouldn't be hard, and i have access to a multimeter. I need a guitar amp, and the owner is willing to give it to me for $50. The speakers in it alone are worth more than that, so I probably wouldn't be losing anything on this.