I have two cablecards installed and only get digital cable channels from one tuner. The other tuner gets all the channels but on several channels there is a picture but no sound. I have paid for and requested full services for both cards. I've tried different cables, audio and video settings without any effect. I swapped the cards slots and the problem appears unique to each card. Installers had the settings reformatted at the home office again without any difference. I suspect it's a CC issue but I don't want to transfer lifetime to this box in case it is a TIVO issue. BTW, my cable provider is CNS (Community Network Services). Not a whole lot of confidence in CNS since they were in awe of TIVO as I was setting it up and showing them the features. I pretty much had them give me the CCs so they wouldn't screw things up.
Rebooting and reinserting the CCs also did nothing.