I have a 4 channel US Acoustics USX-4065. Ive had it since May. I was listening to my music and all of a sudden the music got lower. I realized that there was no more music coming out of my rear right speaker. I did some troubleshooting. This is what I did. I pulled out the fuses and they looks to be fine. I switched them and put in one at a time in each slot and the everything was still working so I assume the fuses are ok. I switched the channel 3 speaker output with the channel 4 speaker output and now my left rear speaker wasnt working and my right one was. SO therefore I assume my amp broke. Now I gotta search to see if I have a warranty but even if I do itll probably take weeks to fix. Is there anything else Im forgetting to check or am I right to assume that one of the rear channel outputs isnt working?