I went to play High Speed last night and I had a buzzing sound coming from I thought the speakers, so I unplugged the speaker and then it sounded like it is coming from the power supply. If I go in to test mode and the playfield lights are off it's fine. So the buzzing only is happening when the playfield lights are on or while it's in attract mode.
What should I be looking for? A bad light somewhere or something on the power supply?