Video displays duplicate image horizontally

Have an interactive exhibit running on Air Run Time on Windows XP.  When video runs inside the player window, the video is essentially duplicated horizontally so the image is squashed and plays two instances of the video top and bottom.  Plays fine on the Mac.  Also, running the SWF file in Flash Player does not exhibit the same problem.  But running on Air on this XP machine displays doubled image. What can be causing this?