I am very happy with my Schaller magnetic pickup, it has plenty of oomf and doesn't feedback. It suits my purposes, (playing in a big band). But I also use my bass for symphony work and when the bass is unamplified, I get a mechanical buzzing/vibration/rattle coming from the pickup. It occurs mostly around certain frequencies, and is very annoying. I sent the PUp off for repairs, an although it is better than before, the rattle is still noticable. Has anyone else had this problem, and come up with a solution?