A not so "noiseless" pickup

[jergato]

I recently purchased a Fender Deluxe Active Jazz Bass (Mexican Made). It came with noiseless pickups. I just discovered a buzz when switching completely to the bridge pickup. This particular model allows you to pan and blend the two pickups together. When I switch to the neck pickup, the buzz goes away. Also, when I touch the strings or the bridge, the noise goes away as well. The noise is most exaggerated when the treble pot is turned up. If I turn the treble down and the bass up, I can at least minimize it.

I took the bridge off and back on making sure the ground wire was connected. That did not help. From what I have read in other forums, it appears to be a shielding issue or a grounding issue. Does this sound right? It is especially frustrating since I purchased this particular model for the noiseless pickups. Can someone shed some light on this issue? Thanks in advance.

[bgavin]

FTR, I've not touched these pickups. They are advertised as dual-coil, which to my understanding is "hum cancelling" same as the DiMarzio dual coil (side-by-side) pickups. If you get hum in bridge solo, and no hum with both pickups fully on, then hum cancelling is not working. This is the classic single coil hum, and how it is identified.

If your bass is new, be sure to take it back to the dealer and present this issue to them. It could be miswired, etc.

I also have a hum issue with my DiMarzio Model J hum cancelling pickups in my MIM J fretless. My issue is a shielding problem or wiring. The remedy is doing a full copper foil shield job with star grounding. I am replacing both volume pots with 500K and the tone pot with a 250k no-load type.

[luknfur]

FWIW:

you might try a search. There have been recent posts regarding the Fender shielding where the cavity shielding didn't run up high enough to meet the pickgaurd shielding so they was no continuity (so to speak). Or something like that.