I've had this amp for about 12 years now. Never a problem. Noticed yesterday the left speaker was silent. It's definitely the amp, and not the speaker or pre-amp output.

Thought I might tear the sucker open and look around a bit. Hoping something obvious jumps out at me. I'm not an electronics tech, but I can follow a logic drawing, use a Fluke, and solder.

Any tips, or suggestions before I start the autopsy? My options for electronics repair are quite limited. Shipping costs would be as much as buying a refurbished unit, I suspect..