The NasaTV UHD channel has always been perfectly viewable on my 920.
Since a couple of days the screen remains perfectly black (no video) while the audio is normally present.
A streaming on PC via webif (VLC) works perfectly (audio and video present) and, always on PC, the playback of a recording is perfectly visible.
On the Dreambox also the recording plays only the audio, while the screen remains black.
Interestingly, if I zap directly to the channel the screen is always black, while if I tune to NasaTV HD and then switch to NasaTV UHD I always get a still image of the video broadcast at that moment.
Below the stream data:
I can't try with an OE2.6 box: can anyone confirm?