Problem with TIVO seeing video signals

[GasX]

I switched cable boxes so I could have HD programming on my new TV. When I hooked it into the TIVO, I started having problems. The TIVO does not see a signal coming in on the basic cable line. It sees the cable box signal, but the line from the splitter is not seen. I have checked the cables and they are fine. Also, when I finish set-up and tell it I will troubleshoot the problem later, it gives an "error 126". At that point I can watch channels 1-99 only...

Did my box go haywire for any specific reason or did an internal connection break while I was banging it around hooking it back up?