My 9 day old NAD 773 needs to be replaced. I can only get analog audio and only via the Tivo unit. Digital board seems to be gone. Plug in any optial cable and the audio is gone. I hope this is a fluke as this is my first NAD component. Dealer is stepping to the plate and will have a new unit installed tomorrow! Other then the hiss issue some are having is anyone else having a problem with the 773 ?