How to Completely Disable Audio & Sound in Mac OS X

Whether you just like peace and quiet or you work in an environment that requires audio input and output to be disabled on a computer for security purposes, it’s fairly easy to accomplish in Mac OS X. We’ll cover how to handle turning off audio for both situations, the first uses mute for basic audio silencing and disabling on the Mac, and the second technique is much more secure and completely disables sound in OS X.

Disabling Sound in OS X with Mute

The most basic approach uses system mute for both audio input and outputs, this is easy to accomplish:

• Open System Preferences, click on “Sound” and from both the “Output” and “Input” tabs click the “Mute” checkbox

No audio will go in or out now, easy enough.

The problem with using mute is that it can be unmuted just as easily, and if you want audio to be completely disabled for security purposes with no chance of a user or third party tool turning it back on again, you’ll have to dig a little deeper and disable some kernel extensions.

Completely Disable Audio Input & Output in Mac OS X

1. From the Finder, hit Command+Shift+G and enter the following path: /System/Library/Extensions/
2. Locate “IOAudioFamily.kext” and “IOAudio2Family.kext” and move them to a safe place for backup purposes, like somewhere in the home directory – you will need to authenticate this change with an admin password
3. Reboot Mac OS X for changes to take effect

On reboot you’ll probably notice there isn’t any sound, and with the audio support kernel extensions gone no audio input or output will work at all with any application. If you want to reverse the change and re-enable audio you just have to move the backed up .kext files to their original location and reboot again. Note that some system updates will replace these kernel extensions on their own, so if you’re in a sensitive environment that requires audio to be disabled then you’ll want to pay attention to how OS updates behave.

What About Muting Boot Sounds?
If you like the idea of just disabling the boot sound but don’t want to remove all system audio functionality, you can silence it on a per-boot basis or mute it completely with StartupNinja.