Freezing During Commercial Breaks

We've been experiencing a very strange situation. When viewing Food Network or HGTV, the TV will occasionally freeze at the end of a block of commercials, typically when the last image is "static" with no moving elements. We have to switch to another channel and back to restore operation. By "freeze" I don't mean pixelation or stuttering; it is as though the programming simply stopped.

This happens randomly, perhaps once every hour or two, and only during commercial breaks. So far it appears to happen only when we are watching Food Network or HGTV.

We have two TVs in our home and both exhibit this behavior. I have tried resetting both X1 set top boxes as well as the modem, but to no avail.

I am uncertain about what to try next.