Ok, so I bought a guitar at the pawn shop (not telling you the price, it was embarasingly low... and it was also half off the embarassingly low price). So I went to plug it into my bass amp (lowest volume settings I could to prevent damage), and the output jack for the instrument is too big! Only by a hair's breadth, but too much for the plug to work. First of all, I don't even know how this is possible when these jacks were standardized in the '40's. Second, is there any way I can tighten it? I can't return it until after the half off sale, but if I try to replace the jack, then they won't take it back. I don't know what to do