I listened to the DD 5.1 and DTS tracks, and they sound awesome. If you don't think a documentary like this can rock the speakers, you're wrong. When the music kicks in, or a performance is going on, the speakers come to life quite well. Not as active as an action packed feature film, but given the nature of the content, and excellent track. No volume issues arise though, and dialogue is always clean and clear.
Extras guess one of the magicians made the supplements disappear, because there are none to found.