Got a HRC in for a shop job. It's doing the weirdest thing. Whenever a lamp in the yellow/blue column is activated, it gives a soft, high-pitched buzz. The buzz comes from the speakers, and it is really kind of annoying in attract mode, when all the lamps are pulsing on and off. It stops if you unplug the speakers, the lamp columns, or the lamp rows. It stops whenever the lamps in that column are not activated. I'm more than a little confused, because the lamps and the speakers are on different boards, and although the power comes from the same place, they really don't interact otherwise. And if it was the power, wouldn't it be on all columns, not just the one? Called Chas but he didn't have a solution. Figure I'd see if anyone here has run across it before.

If you're confused about what's happening, check the video with your speakers up: