p.s.

I have turned off all "sleep" options for the monitor, under Windows 10 power settings.

I have tried booting from a fresh install of Windows 10 on a blank hard-drive with only WOFF installed as the first program and it does the same.

I have tried using the DVI output on the video card (a DVI to HDMI cable instead of an HDMI to HDMI cable) it does the same thing.