Let me start out by saying I loved the sound of this amp. This is my first GK product but I have used them in backlines before. Electronic circuits fail sometimes. I subbed for a gig at a small club in Maryville, TN (Brackins Blues Bar) over the weekend. After about 45 mins I ended up playing direct through the PA. I usually would have had a spare amp but there was no room on this trip. I had used the amp twice before (gigging) with no problems, nothing but compliments on how good the bass sounded. I think I might have sold a MB212 II for GK to a keyboardist after he lifted up my amp during a break. I don't think I was pushing the amp too hard. The Master was at 12, Gain at 11 and all the EQ's were at some point less than 12. Boost was at about 10. Contour was off, horn was off and Limiter was on. Does anything look wrong with these settings? The amp never went into "protect" mode with the red light on. It just went dead. I payed over $400 for this amp on 5/7. Even though it looks like a brand-new amp, I bought it used, so I know that I am hosed on the factory warranty. I have used an amp repair company in Nashville for my other rigs but their turnaround time is really slow so I'll be contacting GK after the holiday for what they think I should do. I'll probably either take it to an authorized repair facility around here (if there is one) or send it back to the factory to get it done right This amp is going to cost me a pretty penny in the long run, but I believe it's going to be worth it. It's that good. And light. I never would have thought the two could go together but when I'm the one doing the lifting I REALLY appreciate that! I'll keep ya'll updated.