I have had my Yamaha DSP-A1 since new and used daily as the main TV sound for 10 years and apart from a few missing character on the display which I have fixed its never skipped a beat. However it now seems to be having an issue with the centre channel whereby it will suddenly go quiet and no output will be heard. I have checked the wiring and the speaker and they work ok so it must be the amp. Ocassionally if I play around with the volume or if a particular loud programme comes on it will kick back in again. It sounds like a loose connection or failing component but I wonder if anybody has any ideas as to what I can check.