I tried to search this first, but didn't find any relevant discussion. Mod, please redirect this if I missed it in another thread. Several years ago we purchased a Kurzweil digital piano. From the start it produced an interference buzz. We have tried plugging it into different circuits, using a direct box, and different cabling between the keyboard and the mixer, but the only way to get rid of the interference is to shut off the lights in the auditorium!
Anyone have a similar problem? Any suggestions.