So I bought this bass on craigslist for 75 bucks because what the heck. It's an early 90's ibanez sr885.
So I have a problem. I tried out the bass and there was this awful buzz, and a continuous low rumbling/popping sound...kind of like what you might hear if you blew into a microphone. I figured there was something up with the pots...so I took it in for repair. They replaced some caps and fixed some faulty wiring in the input jack, which got rid of the buzz, but the rumbling/popping persists.
What I'm wondering is if the issue is not in the pots/caps but in the pickups themselves? Could old/damaged pickups be the source of the problem? If so, would they just need to be rewound, or fully replaced?
It really could be the pickups. Some of the Ibby pups have issues with wire having bad insulation. After (many) years the insulation falls off and the copper makes electrical contact with the magnets and / or short circuits some windings. To my knowledge the SR885 has covered pups, so it's not possible to quickly measure the resistance between the magnets and the windings. I think a good luthier should be able to pinpoint the cause of the popping and rumbling. The repair shop who have worked on it clearly haven't checked their work properly, otherwise they would have addressed the issue.
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Just a cover of a real bassist Beaten and beaten up by time
I'm not familiar with that model? Does it have piezo sensors (generally on the bridge saddles)?
I had a couple of guitars with piezoelectric pickup systems, and it was easy to get them to rumble just like what you describe.
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TC RH450 #8, MM Stingray #153, EBMM SUB #15, Warwick #325, OLP #13, G&L #411
Attack of the killer rumble! Help! 
