I get this problem too. Not always, but fairly often. I have to close the program and re-enter it. If I watch the same battle, it may work perfectly fine or it may go to black screen again. No pattern seems to exist.
I have Win 7 (all updated)
16gigs DDR3 Ram
The game is installed on one of my SSD's
I have a GTX980 (Currently I have my SLI disabled and card removed due to a conflict with another game, or I'd be running it in SLI with another 980)
I also am playing with a custom race. I have one monitor, and all my drivers are up to date as well.