While playing my bass, I noticed my D-string was flat, so I kept twisting the tuning knob little by little, but heard no difference in pitch. Eventually the post the string wraps around snapped off from the rest of the mechanism. One of the following days I went to my local shop and bought a replacement tuner. I figured I'd just do it myself. Simple, right? Well, not so much... I took out the screw in the back of the old, broken tuner very carefully, being sure not to ruin the wood to the point where the threads of the new screw wouldn't be able to catch. Despite this, the new screw won't stay put. The walls of the hole where the screw is supposed to sit seem to be completely flat and smooth, so there's no possible way a new screw will fit in like the old one, because the screw threads have nothing to sit in. I've had this bass since autumn of 2006; is 4 years considered pretty average for tuner life? I also had my B-string tuner break the same way on me just a couple months ago as well. I'm expecting them all to go sometime soon now, but who knows if this problem is even repairable. Also, before anyone asks, I havn't used any freaky tunings or made any radical adjustments to the truss trod or anything like that. I've always used BEADGC tuning. Anyways, I don't think this is at all repairable, but if it is, I'd like to give it a shot. I'm thinking I'll just have to buy a new bass, but if that can be avoided I'm all for it. Thanks for the help everyone.