Cable shows glitch, on demand and streaming shows fine

We have been dealing with an annoying glitching picture for awhile. The trouble seemed to start after there was some work done on our street. We have had the signal refreshed, got a new box, router, and cables from Xfinity, rebooted, we have tried EVERYTHING!
this only happens to regular tv shows. On demand shows and programs on Netflix and Amazon Prime are great, absolutely no problems.