When I got my Premiere units last year, I connected one with component and the other with HDMI, and both worked beautifully. (Both TVs are 720p native.) Well, on the front TV, I'd like to use the component for something else, so I ran a new HDMI cable above the fireplace. When I connected it last night, I got an SD image of "Tivo is powering up," but then it went back to black and No Signal. I tried different inputs to no avail. I switched back to component and everything is fine. I tried pressing the Format button while on HDMI, but it didn't do anything. (That button's just for analog, right?) Now, I've never used these cables (I know, I should have tested them before installing). I've also never used the HDMI inputs on this TV, nor the HDMI output of this TiVo unit. So lots of unknown possible failure points here. My next step is to borrow an upconverting DVD player to test the HDMI (I don't have any other HDMI devices). Any other things to try or other thoughts? Thanks.