Xfinity app DVR playback video pausing issue.

For the last week, I have noticed several of my DVR movies are having playback issues. It first started when I noticed a 3 to 5 second pause in audio, during video playback, especially after the start of the playback or if I tried to fast forward past commercials. In the last four days, I’ve noticed that it will just not play, but about 20 seconds of a video, buffer then crash. 
How can we fix this issue?