It’s only by phone. They won’t answer quickly, and when they do, they never have a useful answer. All they can do is read from the same useless webpage that is available to the customer already. They ask for a phone number “to call you back if we get disconnected”, but don’t actually ever make that call-back. And when you’ve finally proven to them that you aren’t as stupid as they are, and are indeed capable of plugging in a TV, they give you a worthless case number, wait a MONTH, and then have some idiot call you back that obviously didn’t even READ the case before he came up with some BS questions to ask, most likely because he thinks he can annoy you into letting him close the case, rather than bothering to fix the problem.
DO NOT BUY A TIVO HD this year. The software/hardware combo isn’t anywhere close to being ready. Support will not help you.