This is something recent that plenty of players are dealing with right now, try this.
Options > Multiplayer > Advanced then uncheck the boxes that say "Film Grain Effect when dead/spectator"
And then you can add this command into your console in-game, or put it in your autoexec folder so that it will automatically enter it when you start the game up.
mat_hdr_level 0
This turns off the HDR. These problems will persist until Steam patches it, as these problems are on their end.
All this info was gathered from other people, so thank them. :thumbup: