My NAD T743 is overheating on startup. This started after I left it unplugged for a day and a half. I have tried the reset procedure of "Video 6" and "source up" button. I have tried starting from the auxillary power button in the rear. But the unit goes to "over heat" as soon as it warms up. What to do?

Audio Players & Recorders - NAD - T743 Receiver