I heard an odd noise yesterday for the first mile or two driving and I think it was coming from the speakers. After backing out of the driveway, I started down the street and there was a noise that sounded like the car was dragging something over the pavement or the tire rubbing against a mud flap or something. I rolled down the window and it disappeared, but I got out to check anyway, and there was nothing. Then I drove around a parking lot for a bit and it was there again, but only when moving, not when stationary. It also sounded like it could be gurgling of an A/C evaporator, but it was coming from the driver left vent area and I had the A/C off. I thought the sound could possibly be coming from the small tweeter. Anyway, after a few minutes, the noise went away and I've not heard it again for a day. I wonder if it could have been the active noise cancelling going haywire, but I've not seen anything about that here. Any ideas?