Same is happening to me. I can count five times it has occurred to me so far.
I'm currently on the latest patch/update. Running via Steam.
Off the top of my head, two times I can remember was:
- After talking with Jack, then heading upstairs to speak with Tali. Game froze as soon as I entered the engineering room.
- After talking with Garrus, Game froze when I went back into the mess hall. Strangely, this wasn't instant. I got about halfway between the hallway between the weapons room and the mess before it happened (if I look at it from a map perspective, this is possibly the loading barrier for the AI core).
As an additional note, every time this had happened to me the audio has glitched out before hand.
The background audio would disappear, characters would have no audio playing when they were talking, footstep sounds were sometimes working, and sometimes not.
So. I wonder if there is perhaps an overload going on in regards to the audio which is causing the freeze?
May or may not be related. I have been able to continue playing even when the audio glitches out and the game eventually fixes itself. But in the same vein, each time I've frozen, the audio was also glitched.