i have a music video in xvid and ac3 5.1 surround, in an avi wrapper. it is letterboxed, and i want to crop it to 16:9, which works excellent. but i would like to render the audio as-is, in surround, preferably in the same file as the video stream. it’s not a matter of do-or-die, i know i can mux them together afterwards with other tools. but shouldn’t a professional program like sony vegas cater to all needs?