As MoFi mentioned I had issue with my first unit. But AR replaced it and no problems since. The manual does mention a "reboot" procedure. I forget how they lable in the manual but you hit mute, the turn it off, unplug it for a length of time ??(it's in the manual) then you plug it in and try again. If you have tried that and still no tunes I would be calling ARC in the morning they were great on the phone. I am at about 375 hours and it should be fully broken in now. Sounds good but some vinyl sound more, dullish than I had with solid state. Maybe thats' warmth??