Rockford P200-2 issues

Im looking at this amp on the bench thats really unstable. Under no load, it passes audio, but the audio is shaking on the scope. I guess the amp is oscillating. With a small load the amp will play for 4 seconds then pop, then play again. I cleaned and tested all the pre-amp controls but that didn't help things.

I dont see these style rockfords much and really have no place to begin. Any pointers?