Have had T763 for two days. Worked perfectly with remote. Went to turn it off at the panel and the power button wouldn't work. All of the buttons wouldn't work.
Wife says check the troubleshooting guide. I said nothing like that will be in there.
Low and behold the last item on the list:
T763 Does not respond to front-panel commands - Microprocessor error - T 763 may have over heated.
Looks like a design flaw to me.
There is no way this thing should over heat. I have 6" to one side, 12" to the other and 6" overhead. Plus the cabinet door is open. The fans are whirring inside the unit.
After leaving it off for a while it works fine and then a few minutes later same problem.
Since most people use the remote, T763 owners should to their unit and try the panel buttons. I suspect this occured the first time I turned it on and didn't notice it.
Can't help you with your NAD problem but I hate it when the wife does that...same thing happened to me one day when I was trying to start a portable generator during a power outage. After nearly pulling my arm off from maaaany attempts at staring it with the pull cord, I gave in to her suggestion of checking the manual...sure enough the fuel shutoff valve was closed...started fine after that.
It doesn't sound like a design flaw, but like a damaged unit. I would take it back to the dealer for replacement.
It's also possible that you have an external wiring fault. I would make very sure you don't have a loose bit of copper in any of your speaker wires creating a short. Simple way to test would be to unhook everything except your front speakers, carefully check their lines and connections, then see if you still get the problem. If not, hook the other speakers back up one at time, checking their connections as you go. If it dies on one of them then you have an idea of where to look. Of course, it could still be something internal to the receiver even then...
Steve, I had the T762 and it had something similar happen. The front display would go wacky and then the remote wouldn't control the receiver nor would the buttons other than turning it off. The machine would still work fine and if I turned it off, it worked fine until about 10 minutes and then the same thing happened. NAD replaced and upgraded my receiver to the T763. No problems since. I think you have a defect that your dealer should replace.