I've played through every map in the game without any trouble, except for Day 21: Lab Rats. Every time I've tried to play that particular map, my entire system locks up and I have to reboot. I haven't been able to determine a trigger for the lock-up. I can be playing for some time before it occurs, but it has always happened before the first objective has been completed, so within a couple of minutes.

Is this a known issue with the map, or am I alone in experiencing it?