Tab Out >> Interfaces Gone Issue

I am experiencing an issue where my PR runs fine the first time I open it, but if I tab out (to fix PR Mumble, or my computer gives me a notification, etc) none of the player interfaces work when I "tab-in". This includes the spawn menu, the caps lock menu, any maps, any vehicle HUDs, everything but the raw graphics of the game. Please advise on how to fix this.
Thanks.