I dunno about that... I bought Pink Floyd: DSOM, and have my receiver hooked up via optical Toslink, and according to everything I was looking at, the PS3 was outputting DD (or perhaps it was DTS, I can't recall). Anyhow, the sound compared to the standard CD portion of the disk (both were accessible) was NOTICEABLY clearer, cleaner, sharper, AMAZING, and I'm fairly certain that the surround mix WAS in fact working.