That amp, the, "RMB-1095" had a bad "Protection circuit" topology and they, "Rotel" re-designed that entire circuit. Complete with a "New and improved" board a few years after the debut of the amplifier line.
I lost a channel in one a few years ago and my "Amp guy" found out about it on a phone call, while ordering parts from "Rotel". So he replaced it also for another $350. Which was the cost of the upgraded protection circuit board + shipping, two years ago. Did they look at this when repairing your amp? Was it mentioned? I think in total it was $680 including a new power supply as well to repair. Which was what goes apparently when the orig. protection circuit fails.