FYI: DVR CISCO RNG 200. Sudden no-playback of MY DVR recorded programs. Was working OK before then suddenly neither the programs I had already recorded and were showing OK before no longer play back. Just getting a black screen. I am able to get the info feature to work but the progress indicator shows the arrow doesn't move. When I tried the fast forward and back feature the display showed the normal 3 or four arrows indicating the fast forward/back but still no picture. I also tried recording new programs and it seems like it ws recording, but still no playback.
My solution: As a last resort I turned the DVR off and removed the power cord from the back of it. Waited a few minutes then plugged the power cord back in, turned the DVR and TV back on and then it worked. The older recorded programs were still in there and played back OK, as well as the newer ones.