AMC's Fear The Walking Dead closed captions aren't displaying correctly

The closed captions for season 8 episodes of AMC's Fear The Walking Dead are not displaying correctly.  Certain lines get displayed on the screen too long, or blink on the screen multiple times in a row, while other lines aren't displayed at all.  It seems to be affecting all season 8 episodes on demand more than a few days after their initial air date.  The problem seems to be limited to X1 On Demand; episodes streamed from the Xfinity Stream website on a PC don't have the same captioning problems.

This is very similar to a problem I reported a few years ago with Fear The Walking Dead season 5.  I can't find that post right now, but that problem was eventually solved.