@circeseye I think I found the solution. A few things:
Turned off windows scaling. It would cut out with any scaling.
Changed my nvidia color settings to 8 bit, 4-2-2, limited.
Matched my nvidia display resolution to the the resolution I was trying to play in game to hold 60fps.
Had no cut outs with those settings. But, I also had success direct to the TV at 4k, RGB, Full. So maybe the C9 can hold that quality and still pass through dolby atmos surround to my receiver. Thanks for the advice you provided.