Sometime early yesterday morning, we've lost all channels on our Tivo Roamio Basic. We have limited basic cable through Comcast and use a CableCARD, which has all been working great since January. The TiVo is still running 20.3.8. The strange thing is that the channels now report a mix of causes for not working. Some report a signal problem (V53) and some report "not authorized". It seems that more channels report "not authorized" than V53. I rebooted the TiVo, unplugged and replugged the coax cable, and removed and reinserted the CableCARD, all of which had no effect on the symptoms. I guess my next plan is to call Comcast and see if they can help. I can't remember ever seeing this kind of issue before in many years of enjoying TiVo. Thanks for any suggestions.