I have the same problem for several days with the TV picture flickering/certain parts of the screen jumping. I thought it was just on one channel but it is on several. It is the same on recorded programmes on the Tivo box as well as live TV. I checked Service Status and apparently there is a Broadband Fault and a TV fault in my area - maybe it's the same for you if you check. However there is no description of the faults so I'll check back later as both faults are due to be fixed at 17:00.
I have also noticed that the TV is slow to respond to changes from the remote and buffering from catch up on iplayer is so ridiculous that it's impossible to watch a program from there, so I don't know if these are related. (BTW iplayer is fine on my laptop)
I actually switched the Tivo box off with the other instructions and it seemed to have helped, but now seems to be slow changing channels again and looking through channels and going to My shows but keeping fingers crossed.
After receiving notification that the fault showing on Service Status (Fault Ref: C01142942) had been fixed, I again ran a test on my equipment which resulted in a message that a reboot of my Tivo box was required. This I did and the picture and response times did improve afterwards.
So it might be worth going to Check your Service Status and if there are no faults outstanding, Run Test.