It is a Marshall Park series G30R CD. I've been looking all over google for a schematic or how to, so yeah any help finding one would be much appreciated. I had thought cracked solder as well, but shouldn't that more than likely only affect one channel, since there is no master volume control? I've been searching for a crack and can't find one. I've tried the headphone jack and speaker both, no difference between them. Also I replaced the input jack with the CD input jack b/c I never used it, but I don't think that should make any difference, just figured I'd better mention everything I could.