Xbox one video goes black but audio continues

[Powderhound123]

I guess this one lives in the Microsoft forum...
Running VLC on xbox one connected to WD My Cloud NAS.
Each time (virtually each time) that I open VLC to run a movie stored on the NAS it will run ok for a while but randomly will keep playing the audio but the screen just goes black. I can rewind or advance, but still the screen stays dark and audio continues to work.
I then have to exit VLC and reload it, or sometimes reboot the xbox. It then works normally.
Strangely, it does this even on a fresh boot up of the xbox when on games are open in background.
I have tried reinstalling VLC from the Microsoft Store and it makes no difference.
It's pretty frustrating....
Any wisdom out there please?