hey, I have an RX75 that was working fine, then it all of a sudden lost most of its volume and now is very quiet and VERY distorted (basically a buzzing sound when I hit the strings.) I tried bypassing the preamp by plugging into the efx loop...but that didn't help. I just wonder if it is a part on the board that has blown, or the transformer. I do not have a way to test the transformer, but I know it has a thermal fuse, so it would seem as though the thermal fuse has blown, but also it seems that there is a resistor missing and a brown spot where it was (former "repair"??). I am simply puzzled as to what could be wrong and really like the amp. Thanks.