I am having the same problem as well. I have had the TIvo boxfor along time and I wonder if the fault is in the box itself. I have tried the usual procedure of rebooting the box but it has made no difference.
Really sorry to hear you're having trouble with your TV service.
I've run diagnostics on your equipment and I can see an issue with your Downstream Power levels that will need to be adjusted. I've sent you a private message (purple envelope at the top right of your screen) so I can arrange an appointment.
Tech fan? Have you read our Digital life blog yet? Check it out