No audio/sound from my MacBook via HDMI?

How old is your MacBook? If you have one that's too old, it turns out that it might not be able to push audio through your DisplayPort, in which case the HDMI adapter isn't going to be able to perform miracles, sorry to say. It's about mid-2008 that the Apple hardware started to support HDMI audio, based on the research I've done, and there's a pretty easy way to find out if your particular device works or not.

Before we do that, however, odds are that the problem is much simpler: your Mac probably just isn't configured to use the HDMI adapter as the audio output for your system when you have things plugged in. Switch that and *poof* you're good to go!

Let's start there and then if it's still not working, I'll show you what to look for in your hardware configuration app to check your HDMI / Display Port capabilities.

I'll start with a frame from a movie trailer (can you identify it for two points?)

It all looks good, but the audio is coming out of my computer even as the video is being fed to the HDTV.

To switch it, choose System Preferences off the Apple menu, then look for "Sound":

The default audio output is "Internal Speakers", so it's no surprise that while we're seeing the video on the TV, the audio is still being piped out of my MacBook Pro speakers. See the second choice down, however? That's what we want, for the Samsung HDTV we've plugged into:

I click on "Samsung" and get an interesting warning message at the bottom:

"The selected device has no output controls". Sounds ominous, but it's not actually. It just means that I'll have to adjust the volume on the TV itself rather than on the computer.

Once I've switched the output audio, it should automatically be feeding audio to the TV so a quick test with the movie trailer should work great, audio and video both. Easy once you realize that it's not an automatic switcher.

Now, if it's still not working, launch the "System Information" application that you'll find in "Applications" > "Utilities". Look for your Audio (Built In) and make sure that there's an HDMI / DIsplayPort Output option, like so:

Mine's ready to go, as you can see. If yours doesn't show this then you might have an older MacBook or other Apple Mac product and might then need to have a separate audio cable hooked up to your TV. No worries, it's easy to do and the back of your TV probably has a dual RCA-style "audio in" jack you can use with a simple audio splitter from Radio Shack or similar to accomplish the same goal. Not quite as neat and simple, but the end result's worth the hassle, I promise you!

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