5.1 Surround Sound output in iTunes

by postbreak

Getting 5.1 Surround Sound output in iTunes can be difficult. There are some hoops you need to jump through to get it to work. This guide is solely for the Mac as I don’t use iTunes on Windows. This guide basically assumes you have video converted for the AppleTV but you could theoretically convert any video into the m4v container with an AC3 audio track. I have no experimented with that however.

Things you need.

  • Surround Sound Receiver
  • Digital Audio Connection
  • AppleTV converted video
  • Perian Installed

First things first. You have to be connected to a receiver with a digital optical cable. Your receiver has to support surround sound as well. You can’t expect surround sound output from a stereo movie sadly.

Now open Terminal and type “defaults write com.cod3r.a52codec attemptPassthrough 1”

Ok so you meet the requirements above then it’s time to check your settings. Open the Audio MIDI Setup application located in ~/Applications/Utilities. You want to change the format to 48000.0Hz and 24-bit if it is different. It’s confusing but you do want 2-channel.

Audio MIDI Settings

The next step is to start playing the movie you want. If encoded properly the movie will have two audio tracks. Make sure the volume is at 100% otherwise you will get horrible static. Press play and then hover over the HUD menu in the video. Change the volume track like in the screenshot below.


That’s it, if you meet the requirements you should be hearing multichannel sound right in iTunes. A word of caution, you need to have the volume of iTunes pegged at 100% like I mentioned above. If you forget this you’ll get static and depending on how loud your receiver is it could scare the crap out of you.

I have not played with any other types of video on iTunes besides that converted for the AppleTV so your mileage may vary if you try something else. Hopefully this helps if you’re trying to get surround sound output on iTunes. I don’t have a clue on how to get it to work on Front Row just yet.

Something you have to keep in mind, you need to turn off SRS iWOW if you want surround sound output to work. In my testing that plugin seemed to kill the output.