Load/drag the file into VirtualDubMod. On the main menu click 'Streams' => 'Stream List' Double click or disable the one you want to lose and click 'OK'. On the main menu click 'Video' => 'Direct Stream Copy'. On the main menu click 'File' => 'Save as' and give the new file a name. http://www.afterdawn.com/software/video_software/video_tools/virtualdubmod.cfm