Middle of the game, end of the game, in the menus, but usually right in the middle of the game... The game just quits. No crash report, no error report, just quits as if I had hit command Q... No way to know when it's going to happen... It just did it to me again, I was just starting the boss round on KF Hard difficulty. Players just gave me a ton of cash after myself and a few others got killed the previous round, the boss round started, and it quit.