I don't know if this is the same problem as with you, but I occasionally experience a loss of video feed. The screen is basically black background with a message (I forget exact words) in blue text. Cycling power always clears this problem up, but sometimes only temporarily (a few hours or days). All other indications (green LED) seem normal.
One of the cameras that I was having trouble with was located farther from an outlet than the included power supply would reach. I had soldered additional wire to compensate. Considering the possibility of low voltage as a result of my cable extension, I replaced the entire length of wire between the wall power supply and plug with larger conductor (possibly 14 guage). Suddenly, I have no problems with this camera. Ever. It has been many months since doing this without a single dropped video feed.
Of the three -932 cameras I now have, only one exhibits this problem any more (and it has been operating continuously now for a couple of weeks without exhibiting this problem). If this happens one more time on the remaining trouble device, I will perform the same modification on its power supply cable. If this clears up the problem, I will report back.
I am still fascinated that larger wire appears to have solved this problem for the other camera.