Hey man, I am a bit late on this but had the exact same problem you are having. My pickups kept cutting out intermittently, shake the guitar and it comes back. I did EVERYTHING and it frustrated me beyond belief. Finally, I figured out that when I was plugging in my guitar cable, it was very slightly touching the grounding wire from the switch to the jack. My moving around while playing was causing the input from the cable to wiggle ever so slightly inside the jack, and every now and then it would hit the braided wire and short out the signal. Not sure if that helps or not, but thought I would share. :)