I have 2 amps from 2002 that likely need repair. I never tested them but got them from my buddy who had no idea what he was doing. I was planning to fix them. I think one had a loose capacitor.
One is an American Made Rockford Fosgate from their glory days.
The other is a Depth Charge that was made in Korea. There are lots of videos on fixing these classics.
Great for someone with a multimeter and soldering iron. Online has videos.