As mentioned previously my surface pro has been playing up recently. The screen starts to flicker if it's been on too long. Usually after playing a game or two for a while. But yesterday it happened when I was working from home. This is an issue as I need to be able to work from home, i'm working from home again tomorrow.
Before going out and getting a new one I called Microsoft and they went through a number of tests. I had to video the screen twice, once on a test screen and once when it was happening in its normal use.
I videoed the test screen and there is a slight flicker but I couldn't replicate the flicker! Grr... I will try again tonight when I get in. Hopefully they will approve the replacement as it's a known issue with the Pro 4.