blacktop p bass pickups humming
ok guys, just bought a used blacktop p bass from a guy off craigslist. Pretty beat up (looks like he wore a bracelet with mini-hammers dangling from it on his picking hand ***) but figured as long as it sounds good. Bring it home and its humming pretty loud. Given that they're supposed to be hum"buckers", I figure they shouldnt be doing that. Kinda weird though. It quiets down when I touch metal like it should. But theres still this weird loud almost squeeling. Kinda like the pickups sound microphonic. It went away when I turned my tv off. But why is it only with this bass? I have two other p basses. One with the stock mim pickup and one with dimarzio model p's and they dont do this at all. I really wish there was a way to describe it. It also goes away when I roll the tone knob all the way off. But comes back as soon as I raise it up the slightest. I checked the ground wire underneath the bridge and it seems to be ok. Made sure it was touching the bridge when I screwed it back down.
Could it be a bad tone knob? I tried spraying contact cleaner in there but it didnt help. Also the jerk failed to mention that he probably spilled soda on it. When I was unscrewing the pickguard I saw that it was sticky underneath the screws. Could it have messed with the pickups?
Another side note, could be nothing. But when I touch the pole pieces, only the top rows buzz (view as if the guitar was on a stand).
any help would really be appreciated. I'd hate to take it to a tech and pay to have him tell me the pickups are bad or something cause I can replace them myself. Hate to cause this was supposed to be the beater rock star bass. thanks guys