No HDMI Sound Under OS X Lion Using A Mini DisplayPort or Thunderbolt Adapter? Quick and Easy Fix For That [How-To]

Most of the people would be very happy with the migration to Lion, but there are a few who might have encountered a bug or two after the upgrade. So is the case with John who could not get the sound to output through HDMI using his Kanex Mini DisplayPort to HDMI Adapter.  For him it meant the days of  him hooking his 11-inch MacBook Air to his 47-inch 1080p HDTV were at an end.

He isn’t alone. Apple’s support communities are filled with threads from frustrated Lion upgraders who suddenly lost the ability to pump sound through their HTPCs. It’s obviously a widespread problem.
The fix is fairly simple, but it might take a few times. What you need to do is flush out your Mac’s PRAM and SMC, in other words reset them.

Follow these steps to reset your PRAM:

  1. Shut down your Mac totally.
  2. Locate (but don’t press) the following keys on your Mac’s keyboard: Command, Option, P and R. Put your fingers over them, but don’t press them yet.
  3. Turn on your computer.
  4. Immediately after turning on your computer, hold down Command+Option+P+R. This must be done before you see the gray boot up screen.
  5. Hold down the keys. If you do this correctly, your Mac will restart and you’ll hear the startup sound a second time.
  6. Release the keys.

Congrats, your PRAM’s reset! Now let’s reset the SMC for good measure. The instructions on doing this vary from computer to computer, but Apple’s got a great support document that explains how to reset the SMC on any Mac you own.

Once you’ve flushed both the SMC and PRAM, allow your Mac to boot properly. Plug in your Mini DisplayPort or Thunderbolt to HDMI adapter, make sure that HDMI is selected as your Sound output in System Preferences and give your Mac a whirl. Your sound should now hopefully be working through HDMI under OS X Lion. Hoorah!

Using the above steps, John got HDMI sound working on his MacBook Air as well as his girlfriend’s MacBook.
Did it work for you? Let us know.

 

Thanks to John Brownlee from CultOfMac

By AdMac • How-Tos • 0 • Tags: , , , , ,