Recently, a "rattle" has developed on my bass that has made playing unbearble. I started a couple of days ago on my E string and has moved to my other strings and intensified. Now whenever I play a note on my bass I hear an anoying rattle that sounds like its coming from somewhere around the nut. Also, If I "hit" the neck of my bass, I hear the same rattle. I am thinking its a problem with the truss rod, but I'm not sure. If someone could tell me whats wrong with my bass and how to fix it I would really appreciate it.