If you play the same HandBreak compressed movie out of your Mac via hdmi to your surround amp it will only play the stereo track if you are using iTunes or QuickTime and I believe this is because of copy protect and Dolby license issues. So if you have an Apple TV it will play the movie with its surround track. This is great because handbreak folds the 5.1 into a stereo AAC track and also encodes the 5.1 mix into Dolby 5.1 AC3 track so both stereo and surround tracks are embedded in the movie file. I export the movie with FCPX as master video with the 5.1 audio then use HandBreak set to atv3 to encode / compress the video. If you want to play your edited exported movies from Final Cut Pro x in surround then it gets a bit tricky. This setup is via PCM 5.1 audio not to be confused with Dolby 5.1. I have been able to output 5.1 audio with Logic Pro and FCPX no issues at all after you setup the audio midi utility for 5.1. I have been using my MacBook Pro via HDMI into my pioneer av amp which is set up for 5.1.

Under Audio at the bottom of the window select 'Digital Out - SONY AVAMP' from the drop down menu for 'Audio output' *You now have 5.1 Channel Surround Sound from you Mac! Go to 'Preferences' and click on the 'Disc Setup' tab. Last set is to go into the DVD Player to test it. Click on each speaker to provide a test tone to make sure each is connect properly. Then select '5.1 Surround' from the pull down menu.

Click the 'Configure Speakers.' button in the bottom right of the window. On the right side it then should say 'Source: SONY AVAMP' On the left side of the window select HDMI. Then go into Applications > Utilities > Audio MIDI Setup. Then in the 'Output' tab, select SONYAVAMP - HDMI Use a Mini Display Port to HDMI cable and connect the HDMI into the Blu-Ray/DVD HDMI input on the receiver and the Mini Display to the Mini Display Port on your Mac. Most models before early 2009 are not able to output multi-channel audio) (*Check first to see if your Mac is capable of outputting surround sound through the Mini Displayport.

OUTPUT SURROUND SOUND FROM YOUR MAC: (simplest way)

Change speaker output for firefox mac