Just having a blank event video issue :

http://dl.dropboxusercontent.com/s/i3prvnn725gfrkp/VP13BlankEvent.jpg?token_hash=AAHWqH3AWJukj7f8yal95jkqcOe0K2WsIcfNJavJIHIvrg&expiry=1402392837

While editing, I got one video source 'seems disconnected'.
Quit and restart VP13 fix the problem...