My friend's been getting triangular blueish artifacts flashing on his screen when he enters the game. It doesn't happen in the main menu. It only happens as soon as he gets in game.
Things he's tried:
Updating graphics card
Reverting to an old version
Lowering all graphics to cursed
Disabled shadow cache from the NVIDIA Control Panel.
He has an EVGA 1080 graphics card with 16gb RAM. Windows 10.
This is a gif of what's happening: https://media.giphy.com/media/ZxphCeOOFEJlPJpKFP/giphy.gif
And to be clear, this only happens in Sea of Thieves. No other game does this. Even a game as intense as GTA 5 doesn't do it.
Please help.