Finally discovered why when in Oculus VR the display would not mirror to my main HDTV. In my case, GTX1080ti Nvidia it is the renderer for reflections in the display menu. If I leave rendering frequency at static the display mirrors no problem, but set to any other render setting results in the mirror to screen failing. I was always setting it to medium frequency. Hope this may help someone else with a mirroring problem Cheers and happy holidays.
