On my Sire V7 Vintage 2nd generation bass, I am noticing a weird rattling, buzzing sound whenever I play loud on the D and G strings. The rattle is most noticeable when slapping/popping these strings. It doesn't sound like a fret buzz, instead it sounds like a screw is loose or something and it kind of destroys the pop sound. The bass is about 6 months old, and I didn't really notice this until now. I went through and checked all of the screws on the bridge, pick guard, etc and they all seemed tight enough. I also tried mounting the strings through the underside of the bass instead of through the bottom of the bridge, and that didn't help. The noise is very difficult to track down, but it sounds to me like it is coming from the bridge. This is starting to drive me nuts. Anybody ever run into this problem?