so, i have a movie in avi format. when i look at the file properties it shows '2 channel.' when i burn it to a dvd and play it on my dvd player, the dvd audio menu also shows it as 2 channels. however, when i listen to the movie, it is clearly surround sound (5.1). i'm not an expert in digital movies and was wondering if this is correct? why would a movie file show as being 2 channel sound and play as 5.1? thanks.