Using your Mac as an HTPC (Home Theater PC) is pretty easy, right out of the box. Hook your Mac up to your HDTV and settle in to watch your favorite movies or TV shows. There is, however, one little quirk that sometimes leads people to think their Mac can't handle movies with 5.1 surround sound.

Let's start by settling that question right off. Can your Mac make use of surround sound in movies and TV shows?

The answer is, it sure can! Your Mac can pass AC3, the file format used for Dolby Digital, directly to its optical audio output.

Plug in an AV receiver that has surround sound decoders (and what AV receiver today doesn't?), and you have true surround sound to accompany your video pleasure.

Where things get a little iffy is with the source material and the software used to play it back. If you pop a DVD into your Mac, and use either Apple's DVD Player or VLC to watch the DVD, then the AC3 track, if present, will automatically be sent to the Mac's optical audio output.

If you have a video file on your Mac that includes an AC3 channel, and you use VLC to view the video, the AC3 information can be sent to your Mac's optical audio output, but it won't be sent automatically. You'll need to configure VLC to pass the AC3 information.

Configure VLC to Pass AC3 to the Optical Output

1. If you haven't already, download and install VLC.
2. Launch VLC, located in /Applications/.
3. From the File menu, select Open File.

1. Select the video file you wish to watch from the standard Open dialog box, and then click 'Open.'
2. If the video starts up on its own, click the pause button in the VLC controller at the bottom of the screen.
3. From the VLC menu, select either Audio, Audio Device, Built-in Digital Output (Encoded Output) or Audio, Audio Device, Built-in Output (depending on VLC version and Mac model).
4. Start your video by clicking the play button on the VLC controller.
5. The audio should now be passed through your Mac's optical output to your AV receiver.

If you're not hearing surround sound, make sure the video you're watching is playing back the appropriate sound track. Many videos have multiple sound tracks available, usually a stereo track as well as a surround track.

From the VLC menu select Audio, Audio Track. If there are multiple audio tracks listed, look for one designated as surround. If you don't see a surround track, but you do see multiple audio tracks, you may need to try each one to see which is the surround track. Please note: Not all videos contain a surround track.

With VLC all set, grab some popcorn, sit back, and enjoy the entertainment.

Published: 2/24/2010

Updated: 7/30/2015