syciprider: besides criticizing my warning, I don't see you've added anything to solving the problem. Way to go
If there's something wrong, people shouldn't be jumping at one of the most sensitive parts first, especially without full comprehension of the problem.
elgranluis: might be that, too (Jay, don't fogret that it's just the nut part of it. If you can reach it and the nut is loose, then tighten the nut). However, when I've had something like that happen, it was rattling with all strings. Also, the trussrod is usually glued into the trussrod-channel, so it shouldn't be moving or rattling, only it's unglued end and the nut.
You can break the trussrod without breaking the fb, expecially with cheaper ones. Also, truss rod's don't just break, but can also get jammed or stuck in, which is also bad.
Might also be a loose neck-joint screw. I have a bass here with a partially stripped screw (just 1 of the 4 screws) and I can hear a metallic high-pitched zzzrzzr sound. It comes out on higher E notes; however, I haven't experienced strange vibrations in the neck. So check if the screws are tight enough (use the right size driver, but be careful not to overstrain them, that's how this one was stripped).