Originally Posted by _fLaK_mOnKeY_
I haven't played the demo yet but I believe there is a legitimate reason for the guy voice. In the full game, your character actually dies somewhere near the beginning. You basically become this disembodied voice able to possess any one of the squad members. I'm not sure where in the game the demo takes place, but I think thats why you hear a guy voice coming out of a female.
Yep, thats why. this demo is about half way through the game.