I have a Toshiba 46HM94. I have the exact same problem. Many visits from Comcast, using Moptorola C/C. Toshiba Consumer Relations (1-800-631-3811) say they are researching the issue and acknowledge a problem. Call them please. I wonder if any Toshiba TV works with the Motorola card??
I recently bought a new Toshiba 46 DLP with and HD tuner. I was told by Comcast that I had to get Digital to get HDTV signals and had them come out to install the cablecard. WHen they did I lost the ability to change channels on my TV with the cable card in. They installed another one and same thing. I am being forced to get a box now to get HDTV which really ticks me off. I do not need another remote!!!
Has anyone had a similar problem and know what might be happening with the channel changing?

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