The following info might be helpful if your HD Comcast box is not working with your Sony Google TV: I recently bought a Sony Google TV -love it! The Comcast hdmi box I had been using with my former tv would not work with the new Sony when using an hdmi cord hookup. The Comcast (non-dvr) box I had that did NOT work was a Scientific Atlantic 4250 HDC. The Comcast box I swapped for that DOES work using an hdmi cord is the: XFinity Cisco RNG150 (non-dvr). Bottom line: Swap out your Comcast cable box if you are having problems with your hdmi hookup not working. (If it's not working you will see a message on your tv telling you to check your input/ you won't be able to watch your tv). If you call Comcast for help (1-800 XFINITY) they will try to tell you the problem is either your hdmi cord or your tv. Take your cable box into a Comcast office and ask them to swap it out for a different brand or model.