I have the plug-in add on hd dvd player for the xbox 360, which i haven't used in awhile. A few months ago I downloaded the new software update for the 360 (the one microsoft launched where you can create avatars) and i am wondering if that is part of the problem. The last time i used it all i had to do was put the movie into the hd dvd player and it would start playing, now nothing happens. i have the hd dvd combo version of 300 (one of the greatest movies ever!!!!) and when i play the regular dvd version on my 360 it plays fine. That leads me to belive there is nothing wrong with the movie. Does anyone have any ideas?