Hello, I just picked up my 14 R/T a few days ago and noticed something today. When I started it up and put the temperature to AUTO, the blower would work its way to the highest setting the warm the interior. Well I can hear a whistling coming from the passenger foot area vent. As I manually lower the fan speed, the whistling slows and eventually stops, but if I crank the fan back to high again it whistles. Anyone have this happen or do you think a trip back to the dealer is needed?