Thank you for answering. The red ligt is on, but no responding when i push the butten. So its maybe the power supply as you suggest. I better deliver it for service. Regards Frank

Hello. I come over a 5500 with master control. The problem is that there is no light in the amp, and not responding from the control. However i can hear a rele` clicking when i connect the powercord. Any clue somebody? Regards Frank