Hi, I hade a same problem like yours. With the latest nvidea video card driver #382,33. disply flickering every 3 seconds and head set led changes from red to blue. I solved it, by switching off / on the head set and start Steam session in the main screen of Pimax 1.2.75. Think the connection with Steam Plattform is the reason for flickering and chaging the color of the LED. When I didn’t use the head set , I switch it off. Starting Pimax, switch it on , wait approx. 10 seconds, head set is detected , after that I start Steam VR. Everything works fine.