Occasionally I buy/rent movies from iTunes, if I really want to see them there and then and think it’s worth forking out money for protected content. But a lot of movie connoisseurs don’t like iTunes because the audio quality is only stereo or Dolby Pro Logic (fake surround sound over two channels). But upon inspecting the content of a movie file, I’ve found an AC3 5.1 track in the m4v container.

It says it’s protected, and when I enable it (and disable stereo) I can’t hear anything. This could be because it’s firing out my optical cable with encryption. When I connect my Sony receiver to my Mac via optical spdif, it should (in theory) be decrypted and played in full surround, right?
Hope so!