Recently, we've been having the following issue:

When attempting to play a recorded program, after playback for a few minutes, the program will freeze, then stop, and the "Network Problems..." message will appear.  After backing out of program and attempting to get back in - all recordings will temporarily disappear.  Eventually, they come back.  Just now, I have tried to watch tonight's recording of "The Walking Dead," but three times in a row, this has happened, and when I'm finally able to try again, it has stopped during the same scene. 

I've restarted my receiver, and I've power cycled my Gateway.  We were recently shipped our 5th DVR, and since then, this problem has gone from rare to VERY common.

Any suggestions how to make this go away??