Yep, I hate to say it, but M$ has done the most illogical thing. It seems there are a rash of problems with the 360. One like your son's as well as overheating problems. The power supply overheats, a quick tweak is just elevating it off the floor so air can cool the bottom.
If I were you, I would just return it. Flat out. Then wait and see if the next batch is without problems.
I guess I am lucky that I am not in the states. Now I feel a little bit better about having to wait.