Just this past week I was driving an 05 outback(Driving a bit hard).
And some how mast up the cars front end one side right behind the wheel it sounded more like a grinding or rubbing noise.
Not sure what is was, the car was a rental so the hertz guys gave us a new one the next day and said they would take it to the shop.
I'm not sure how much different they are in the AWD.