I am installing a pair of 52 Pure Vintage pups in my tele build. I am using a 920D Custom standard 3 way harness. The bridge pickup works as expected, but the neck pickup only makes a low humming noise, no actual sound. I can't see what I might have screwed up. I soldered the pup to the blade switch and the ground to the pot where the other grounds are. So is there something I am overlooking or is this pup just non-operstional? Thanks!!