Originally posted by Slack
Actually it sounds like a similar problem that some people have had with the stock wrx muffler. Time for an aftermarket exhaust!
Um, the guy has a brand-new stock TS, and not a WRX. Also, the "whistle" that people have with the WRX muffler is when the shut off the car. The final "puff" of exhaust from the engine causes the muffler to whistle.
mr_yellow - it could be that even though your car is new, you've got a bad wheel bearing. Does the "whine's" pitch match the speed of the car, or does it follow the RPM's of the engine? From what you've posted, it matches the speed of your car.
Sounds like a wheel bearing to me.