Disable Audio Sound on Mac OS X Completely

To silence a Mac, turn down its output volume and mute alert sounds; for the strongest practical silence, also disconnect audio devices and check apps that can play sound independently. These steps cover older Mac OS X systems as well as newer macOS versions, though menu names may vary slightly.

What You’ll Need

Access to the Mac and its keyboard or mouse.
A moment to check external speakers, headphones, displays, and audio-playing apps.

Step-by-Step

Turn the output volume all the way down. Click the Apple menu and open System Preferences (called System Settings on newer macOS). Choose Sound, then open the Output tab. Select the Mac’s built-in speakers, if available, and drag Output volume fully to the left. If you see a Mute checkbox, select it. On some versions, use the volume keys on the keyboard to reach zero; confirm the volume slider in Sound rather than relying only on the key presses.
Mute system alert sounds. In Sound preferences, open Sound Effects. Set the alert volume to zero or select Mute, if that option is shown. If there is a setting such as Play sound effects through, choose the intended output device and keep its alert volume muted. This prevents notification and interface sounds, but it does not necessarily stop music, videos, or sounds inside apps.
Check which output device is active. Return to the Output tab and look at the selected device. A connected display, USB audio interface, Bluetooth headset, or external speaker can have its own volume control and may not follow the Mac’s built-in-speaker setting. Lower or mute that device too, or disconnect it if you do not need it. For Bluetooth audio, open Bluetooth settings and disconnect the headset or speaker.
Silence apps that are already playing. Pause audio and video in browsers, music players, video-call apps, games, and presentation software. Mute each app’s player or call controls where available. Closing or pausing a browser tab is important: system alert muting does not mute web-page audio, and some apps remember their own volume separately.
Disconnect audio accessories you are not using. Unplug headphones, speakers, USB audio devices, and audio cables from the Mac. Check a monitor or dock as well; it may route sound to speakers of its own. If you need an accessory connected for another purpose, mute its physical controls or select a different output device and verify that the accessory is not still producing sound.
Test quietly before relying on the setting. Keep the output slider at zero and trigger a harmless alert or play a short, low-volume test clip. Check the Mac’s speakers and every connected output separately. If you hear anything, stop playback immediately and repeat the device and app checks. Do not raise the volume just to test if silence is essential in that moment.
Recheck after restarting or reconnecting devices. Macs may switch to a newly connected display, headset, or speaker, and some applications restore their previous volume. After a restart, waking the Mac, or connecting an accessory, revisit Sound settings and confirm the selected output and mute state.

Common Mistakes

Muting alerts but not app audio: Sound Effects controls notifications and interface sounds, not every application’s media playback.
Assuming the keyboard mute key covers every output: The key may affect the selected device, while a monitor or powered speaker has independent controls.
Muting the wrong device: The Mac may be sending sound to a headset, display, dock, or USB interface instead of its internal speakers.
Using zero volume as a permanent guarantee: A device change, app setting, or restart can alter the active output or restore audio. Check again when circumstances change.
Confusing silence with disabled audio hardware: These steps mute playback; they do not remove audio capability or prevent a user or app from changing the settings later.

Tips

For quick muting, use the keyboard volume controls, then confirm the on-screen volume indicator or Sound settings show mute or zero.
If the Mac has a physical headphone jack, plugging in headphones can redirect sound, but it is not a dependable mute method: the headphones can still play audio.
Before a meeting or presentation, mute the computer and the output device, then pause media and check the active app. This helps avoid unexpected playback.
Keep a note of your usual output choice if you frequently connect displays or Bluetooth audio. Restoring the preferred device is easier than troubleshooting an unexpected one.

Troubleshooting

Sound continues after the volume is set to zero. Open System Preferences > Sound > Output and confirm which device is selected. Mute that device directly if it has controls. Check that the sound is not coming from a separate phone, television, dock, or speaker nearby.

The volume control is unavailable or will not change. Disconnect external audio devices temporarily and select Internal Speakers or the built-in output if listed. If a Bluetooth device is connected, disconnect it and check again. Restarting the Mac can clear a temporary audio-routing problem; after startup, verify the output and mute settings before playing anything.

Only one app keeps making sound. Find its player, call, or notification controls and mute it there. Pause playback and close the app if needed. A browser can have multiple tabs with audio, so inspect each active tab rather than assuming the system alert setting controls them.

You still hear alerts. Check both the Sound Effects alert volume and the app’s own notification settings. Some apps control notification sounds independently. Also confirm that alerts are not being played through an external device that has its own volume.

Settings keep changing. Recheck the output after connecting or disconnecting a display, headset, dock, or audio interface. If the problem persists with no accessories attached, restart the Mac and test again. On an older or managed Mac, an administrator or configuration setting may restrict audio controls; contact the person who manages the computer if you cannot change them.

Frequently Asked Questions

Can I disable all Mac audio with one setting?
Usually there is no single setting that blocks every possible sound source. Muting output, muting alerts, and silencing apps and external devices together is the practical approach.

Does the Mute key silence notifications too?
It may mute the selected output, but check Sound Effects and app notification settings as well. Behavior can differ between Mac models and system versions.

Will muted audio stay off after a restart?
It often does, but do not assume it will. Recheck the output device and volume after restarting or reconnecting audio hardware.

Can an app play sound when system alerts are muted?
Yes. Media playback, calls, games, and browser audio can have separate controls and may still play through an active output.

How do I restore sound later?
Open Sound settings, select the desired output, and raise its volume. Unmute Sound Effects and any apps or accessories you muted.

Does this permanently disable the Mac’s audio hardware?
No. These steps mute playback without removing or permanently disabling the audio hardware. Anyone with access can change the settings again.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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