When I use my Dell mixed reality headset with my Alienware 17 r4 laptop connected to an Alienware Graphics Amplifier with a gtx 1080 ti card (headset hdmi and usb connected to AGA) it works great for ~5 minutes, then I get the odd 'white flash' through the headset. If I am playing a game like assetto corsa that also displays on my laptop monitor I do not see any flashes on the monitor, just the headset. If I continue on these flashes increase and finally the headset display blacks out. If I shutdown the mixed reality portal and start it up again it works fine for a while but in time the white flashes return.
If I remove the AGA and go back to my laptops internal gtx1060 everything works fine again (after an extra restart). So, right now my AGA and 1080 ti are not usable for Windows Mixed Reality. Very disappointing, esp. after the cost of both of these. Also, the very small performance increase with the AGA/1080 ti for non-VR does not make it worthwhile to switch back and forth to.
All my drivers and bios are up to date. I have also contacted Dell Support but their early response is that this is a 3rd party WMR issue and they are not sure what they can do. They will be passing this onto one of their development team guys so maybe he/she will be able to help.