My TivoHD is showing only gray/white screen output when on live TV. It is not recording anything as well. It's almost like it is not connected to the cable input. But, using Settings>Cable>Signal Strength shows that there is plenty of input strength, typically 95+. Now Playing is fine, so Tivo does output (HDMI) to the screen. I've tried a power cycle a couple of times. I've tried pulling and reseating the m-cablecard. My cable line comes in to the house, splits to two. The other line is connected to a same-model TivoHD and it is doing just fine. Any suggestions to look for in debug??