Okay, I'm just going to start off by being totally honest and be at your mercy here. I am not an electronics guy, though I would very much like to be. I am fascinated and dumbfounded when I attempt to learn about this stuff. I am, however, a musician; a musician with an electronics problem. I have a Marshall G50R-CD solid state guitar amplifier that started acting up about a couple months ago. The signal was phasing in and out and I was losing most of my volume. But it would only do this when the volume was turned up around 4 or so... I opened it up and found a component that was loose. The solder joint had come apart, so I re-soldered it and it worked as good as new... for a while anyway. A couple weeks ago it started doing it again, only this time the signal wasn't just fading, but cutting out completely. I opened it up again to find a little wiggle in my solder job, so I re-re-soldered it and put it back together again. This time when I hooked it back up it sounded perfect on the distortion channel but was scratchy or staticy when I would strike a string on the clean channel. (I'm assuming it actually does this on the distortion channel as well but the distortion hides the static.?) I don't know what the part is that keeps coming loose, but it's a white rectangular component about 1/2" tall and wide by about 3/4" long near the end of the circuit very close to where the wires go out of the main speakers. There are two other identical to it right by it and surrounded by a couple of large cylindrical capacitors. I hope you guys can help me. Everyone else keeps telling me "take it to an amp tech," but they usually like to work for money and I don't have any of that lately. I sure hope you guys can help me.