Was wondering if its ok to set up both a comcast box and cable cards or if thats the kiss of death. I've set up my series 3 that way do to the problems with the cable cards receiving premium channels. Now the tivo box keeps shutting down with all the displays on the front lit up but nothing coming thru to the tv. I power cycle the tivo and that works for maybe an hour then shuts down again. is the problem running both boxes? Love my tivo but also like on demand, am I asking for too much?