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The first time is on Mission 4 (Lab Rat) where you had to fight the helicopter in Gould's lab. I got killed by the helicopter's missiles and when the game re-loaded the level....it froze up. After I turned my Xbox 360 off and back on and then tried to restart from my last save point....the game would just freeze up after the level loaded up. I went to the mission select and selected the mission, that I was on, then it worked fine again.
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Anyways, it seems like others are having freezing problems as well. I really hope that the development team will look into this and fix the problem(s) as soon as possible.
+1 on that , I have not played through the level again though. This happened me randomly twice, but booting back in worked. On the Lab rat mission, the freeze is total and needed a level restart.
I am torn between returning the game for the fast return deal in Game, or wait for a patch.
option 1 seems to be the best one. As fantastic as this is the truth is that I cannot handle locking , sticking and crashing on console. I returned Mirrors Edge for the same reason.