The amp.

It's not plastic shit so the metal got hot ut it never melted. I would have not even noticed it on fire if it didn't pop.. it was contained inside the unit. I unplugged it, which did nothing. If it's playing music, it'll stay on at the same volume, distortion level, and quality for 15 seconds before it quickly fades off. So it was on fire for about 20 seconds after I unplugged it.. during which time I'm sure the board melted itself beyond anything I can solder back together myself. poor amp.

It's about 20 years old so I guess it was just time.