I am not a savvy tech person which is why I chose to use a prewired preamp (only the hot leads from my 2 PuPs needed to be added and their grounds (along with the ground from the bridge) needed to be handled. I bundled the grounds and soldered them to a pot and crimped the hot leads to the appropriate wires on the stacked Volume/Blend pot. I get a pretty nasty hum unless I'm touching the strings, PuP poles, Bridge or any of the pots. It then goes dead silent. I also notice I get just a bit of a "crackle" for a moment if my wedding band touches the strings (haven't tried other components). Finally, I had shielded the cavities with copper foil that is supposed to have conductive adhesive and while I haven't connected the foil between cavities I swear that touching the foil will actually make the hum louder with a "click" upon initial touch. My theory is my shielding is borked and somehow I have a bare wire in contact with it somewhere. If anyone else has some pearls of wisdom, I am all ears! tnx!