Well, AC3 doesn't quite work that way. To get just the corrected section, you have to take the whole enchilada, then strip out the video and audio streams to their separate elements, then put them back together using the new audio file. Then rebuild the menus and chapter stops. Quite a process actually, so for a forty cent disc and a 37 cent stamp it's easier to pay a whole disc forward. Funny that a movie can be manufactured and shipped for under a dollar and the industry is crying about lost profits.