Video will not display, ride starts but screen stays black on downloaded or streamed video.

I recall having this issue last year, too. I've downloaded videos and they will not display, I've streamed videos with the same result. 

Widgets all work, and everything is connected and tracking; there is just no video.

How did this all work when it was Tacx, but now it's hit-and-miss... How can this be fixed? Any help please.