Green/gray screen with buzzing noise looping when playing Leugue

Hey everyone :) So I have this problem when I am playing in game, and it happens randomly. My screen will all of a sudden go grey or green, and than a loud buzzing noise will follow and that noise will loop. I thought it might be my rig but I just got a new Gtx 750ti graphics card and when running TF2 or any other type of game I do not experience this problem. I'm not sure if the problem is on my end or on Leagues end. If anyone has any insight or knows how to fix this problem that would be well appreciated. Thank you!