If you are experiencing a lack of sound since upgrading from OS X Snow Leopard to OS X Lion (and beyond) on older Macbook models, the problem may lie with Intel High Definition Audio.
The simple steps below detail how you can see if this is the root cause of the issue.
NB: In order to follow this guide, you will need to comfortable opening a Terminal window in order to execute a simple command.
Here are the steps in order:
- Open System Preferences
- Go to Sound
- Click Sound Effects
- Tick the box for Show volume in menu bar
The volume icon should appear in the menu bar (towards the top right of the screen). It’s probably greyed out at this point, but launching terminal and typing the following command should see it become available again:
sudo killall coreaudiod
Sound output should now have been restored.
If this didn’t fix your audio problems, or if you need to restart Intel High Definition Audio for any other reason, launch Terminal and type the following command:
sudo launchctl load /System/Library/LaunchDaemons/com.apple.audio.coreaudiod.plist
Further information of Intel High Definition Audio can be found on Intel’s website: