I have an Epiphone Les Paul. While playing on the neck pickup, the volume sometimes drops out to about half, then back up again. This started happening recently, and it happens approx once every minute. I thought there might be a loose wire so I opened up the back and all the soldering and wires on the pots look secure. Does anyone recognize this symptom of the volume dropping in and out on one pickup? Not totally out... just dropping to half, then boosting back up - apparently randomly. Or is there a way to test whether a suspect component may be the culprit? Thanks in advance for the benefit of your experience!