I have a RS-TX20, Comcast cable box with wireless modem. The past few months when I turn it on, I often find the TV screen frozen and on a different channel than I left it on (I live alone). I have all but stopped using my Tivo to record because it nearly always freezes when I do schedule a recording--but not ALWAYS. To unfreeze, I have to unplug and reboot. I'm not very knowledgeable about electronics but would appreciate any suggestions. I do NOT have TivoPlus.