Unused audio files in the code for a videogame? No one's ever heard of that before! What is the point of this? For all we know these could be files from the Reach code--the entire Halo franchise is after all built on the same engine as the previous one. I don't recall any one ever complaining that Halo CE still had the codes for Engineers buried within, but I guess back then people didn't look for every reason to waste energy hating a game.