We chased similar trouble at a local Harley Davidson shop and finally caught the culprit when I noticed a shop tech leaving for the day. Just before he walked out the door, the problem stopped. We had him go back into the shop and turn on everything that he had just shut off. Turns out that they had hooked up a new neon girly sign on the backside of the wall that the KSU was hanging on. The only access to the shop was outside this showroom and through a locked gate, so it just didn't jump out at us immediatly. Look at what is on the other side of the wall, just to be sure there isn't a microwave or Pamela Anderson all lit up.