I have the exact same problem and it only started happening after today's patch.
I join a server, spawn in and run for 10-15 seconds, then a black screen appears and the loading thing in the top right corner keeps moving.
After a couple of seconds of that black screen the game just closes down. No crashing, no error messages, nothing.
I tried uninstalling/installing punkbuster, uninstalling/installing DirectX, checked my ports and everything is as it always is.
What did you do, DICE and how do I fix this? It's getting extremely tedious that there's problems with _EVERY_ single patch.