I've got a Jazz bass i've been toying with and I'm getting this buzz out of it. It's annoying, but in a full band setting not a terribly big deal. Anyway, it just buzzes when I have the tone up past 0, and if it is up all the way (the way I like it) it buzzes but will stop if i put my fingers on the control plate. Is this a grounding issue? I just changed the pots to 500k and it's still happening...the cavities and pg are shielded and I've got the input grounded to both the bridge and a grounding screw. Thanks in advance for any help.