Horrible Killing Floor Performance after Halloween Update

[Aegrus]

I googled it and couldn't find anything, so here's my problem. After some of the recent Killing Floor updates (adding news guns, adding new dlc, starting the Halloween event) my frame rate died. I used to get 60+ fps on ultra with my 6770, and when I upgraded to my 560 super-clocked, my frame rate obviously got much better (as in, 100+, though I still cap it at 60.) However, after the updates, I'm lucky if I keep a stable 40, and it sometimes dips lower. I can play at 30-it's not game-breaking or anything, but it bugs me that I should be getting far better performance, and I'm not. I validated the games files and two of them were repaired. I also turned off Skyrim ambient occlusion, (which I was for some reason enforcing, lol). That actually brought my performance up to about the stable 40 I'm getting now, because I used to be at sub-20 frame rates immediately after the updates.

 

My ping times are as low as ever. (20-50) I'm considering just re-installing it.