I am taking photos of my '75 Precision in anticipation of selling it within a few months, and it worked fine before I disassembled it to take the shots. When I reassembled it and plugged in in, it's malfunctioning. First off, the pickups are live when the volume knob is in the off position...that in itself is a mystery. Secondly, it doesn't sound even close to normal when it's generating sound from playing the strings. I just took the pickguard and pickups off and looked at all the connections and can't see anything at all that looks out of place. Where do I start, and what do I do, to find out what the problem is? Thanks!