I know P90 pickups are noisy (and especially vintage ones) but my guitar has been extremely noisier than usual. It sounds as if it is picking up a strong amount of interference, and I have tried the guitar in multiple places with different amps and cables. I even tried turning off everything in the room to make sure nothing was coming from lights, fans, or other gear. Also, when both pickups are on, they are wired out of phase, and should cancel out the noise. Instead, the noise is twice as strong. The noise will decrease along with the volume knobs and dull with the tone knobs though. I checked the electronics and there are no loose wires inside. The only thing I could think of is that I took a piece of rotting black tape out and replaced it with new electrical tape. Was that a sort of shielding tape. What is going on here? I have a lot of experience soldering so I can handle most repairs this could require. Thanks.

Make sure your bridge ground has not become resistive or disconnected. Connect a clip lead from your bridge to the ring on the jack ground. (does the buzz stop?) Or.. Measure it with an ohm meter. It should read close to zero ohms.

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Stage Guitars: '80s Thin line LP Custom, '70 LP Standard, '83 Squier Black Headstock Strat w/ Dan Torres pickups, '59 Black Danelectro DC, sometimes others.

Pedal Board: Nady UHF 10 -> TU2 -> Rocktron Big Crush -> 70s MXR Phase 100 -> Cry Baby -> Bad Monkey -> Early '80s Rat -> Early '80s Ibanez CS 9 -> Ibanez DE 7 -> Behringer Dr 100 Stereo Reverb

Stage amps: '63 Blonde Tremolux w/ two original 2X10 cabinets with a '60 Ampeg Rocket/18 watt VTB Marshall clone/ Epi VJ into a Mashall 1965A

I tried both. I was reading very close to 0 ohms. Still that noise...Also replaced the electrical tape with super 88 stuff just to be sure.