Runtime Error

I've recently just started playing UT3 Black after it being on my list for a while. Sadly though, I kept getting runtime errors on a few maps in campaign and quick games. After 10 or so games though, the playable maps started getting runtime errors too.
I've googled around and tried deleting a few things that were suggested (cache, evil file in effects folder, etc) and my system is freshly installed and up to date.
Anyone have any tips on how to deal with this?