Annoying Glitch

So when i play frhd sometimes my screen will start doing this weird thing where it zooms in and out super quickly. Like it's flashing from zoomed in to zoomed out. And if im on track editor it will do this and then turn completely white. Can someone please help? Also sometimes when im on the editor it will flash white every couple seconds and my player's head will be gone. It only shows when i die, but even then it's only a grey dot. It makes making tracks difficult and annoying. PLEASE HELP!
Information:
Im on mac osx
Google chrome fully updated
i made sure only one tab of frhd was open and it still happened