Stutter when watching NasaTV UHD

[0ryn]

I have a Zgemma H9.2 box. It works perfectly accept when I try to watch NasaTV UHD on 13E (Hotbird)
The picture plays normally for around 6 seconds then its pauses for about 2 seconds then resumes playback stuttering for about 2-3 seconds then you get 6 seconds of normal playback.
Any ideas?
I'm not using a UHD monitor to watch it. I just want to watch the UHD for the program content.

I'm a bit of a new old hand to this. I last played with satellite TV when D-Boxes were the thing to have. I used to run enigma images and do silly things like show the tv picture on the mono matrix front display.