I'm really lost on this one: I have an AVI file that I converted to mpeg2 (for a dvd) with ffmpegx. The resulting file won't play in Quicktime (doesn't open), but will play fine in Mplayer and VLC. ffmpegx also spit out a VIDEO_TS folder which doesn't play correctly in OS X's built in DVD Player. The video is choppy and doesn't sync up the audio. When I play the .vob file in the VIDEO_TS folder in Mplayer or VLC it plays fine. I had ffmpegx also create an .img file that I burned to DVD using Disk Utility. I put the DVD in my Vista Media Center and the same issue happened as with OS X's DVD player. When I play the DVD in my Samsung DVD player, the video is smoother, but the audio is off. Playing the DVD in my girlfriend's [Samsung] DVD player, the audio cuts out every once in a while, but they are closely synced (not as well as the original file). This happened with two separate files so i'm not sure what is causing it. Any ideas? I used Vista's build in DVD burner to burn a different file and it played fine except my Samsung DVD doesn't see the 5.1 audio track :-(. It does with the DVD from my Mac.