I've tried that including the thump to the control box near the computer
I checked the incoming power with my meter. The 3 led's on the power supply board are all lit and the green pass or fail light is lit. Their are two fuses on the power supply board and their lights are not lit, although I haven't taken the fuses out to physically check them. The machine is 8 months old with 600 hours on the clock, go figure.