If you are having trouble playing sounds and choosing an audio device on your Mac, you can try some quick fixes before going to a Genius Bar. Often times, just removing and reinserting some headphones to get everything working again. You can also reset the PRAM, correcting many audio-related problems. Finally, you can update your operating system to the latest version of OS X, to fix problems caused by system errors.
Steps
Part 1 of 4: Simple Remedies
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Step 1. Restart your computer
In some cases, a simple restart can correct audio problems. When something isn't working as it should, try this solution right away.
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Step 2. Plug in some headphones, then remove them
If the volume controls are gray and inaccessible or if you see a red light coming from the headphone jack, insert and remove the Apple headphones a couple of times. This remedy has proven effective for other users.
- Note: This problem is a sign that the Mac hardware is about to fail and you will probably be forced to take this remedy more and more often, until a component is completely broken. For the problem to be resolved completely, you need to bring your computer to technical support.
- Some users have been more successful in this procedure using genuine Apple headphones.
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Step 3. Download all available updates
There may be a hardware or system update available that will correct your problem. Click on the Apple menu, then select "Software Update", to search for and install updates.
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Step 4. Open the Activity Monitor and stop the "coreaudiod" process
The Mac audio manager will restart:
- Open Activity Monitor from the Utilities folder.
- Find the "coreaudiod" process in the list. Click on the "Process name" column, to sort the list in alphabetical order.
- Click on the "Abort Process" button. After confirming your choice, coreaudiod will be closed and restarted automatically.
Part 2 of 4: Check Your Devices
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Step 1. Make sure the headphones are not connected to the computer
In that case, you would not be able to hear audio from the system speakers. Try plugging in and removing the headphones to see if this will wake up the speakers.
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Step 2. Click on the Apple menu and choose "System Preferences"
If multiple audio devices are connected to your Mac, your computer may not select them correctly.
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Step 3. Click on the "Sounds" item, then select the "Output" tab
You will see the list of devices that can play audio.
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Step 4. Select the correct output device
Choose the one you want to use to play computer sounds.
- If you want the Mac speakers to play the audio, select "Internal Speakers" or "Digital Out".
- If you are trying to make a TV connected to your computer play the sounds, select the "HDMI" item.
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Step 5. Check the volume of the external speakers
Many audio playback devices have independent volume controls. If the speakers were turned off or at very low volume, you would not be able to hear any sound, even if they were the selected device.
Part 3 of 4: Reset the PRAM
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Step 1. Turn off your Mac
By resetting the parameter RAM (PRAM) you can correct many problems related to volume control and sound reproduction. Some settings will be reset, but your data will not be deleted.
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Step 2. Turn on your Mac and immediately press ⌘ Command + ⌥ Option + P + R
Keep holding those keys until your computer restarts.
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Step 3. Release the keys when you hear the startup sound again
The computer will continue to boot normally. Please note that this startup mode takes longer than normal.
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Step 4. Check your audio and other settings
Check if the system plays the sounds correctly and if you can adjust the volume. The computer clock may have been reset by the operation, so remember to reset the correct time.
Part 4 of 4: Update to the Latest Version of OS X
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Step 1. Check if your computer is running the latest version of the operating system
OS X Maverick (10.9) had many audio issues, which were fixed by the Yosemite version (10.10). With El Capitan (10.11) even more bugs have been fixed.
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Step 2. Open your Mac's App Store
Operating system updates are free and available on the App Store.
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Step 3. Click on the "Updates" tab
If there are any updates available, you will find them here.
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Step 4. Download the latest version of OS X
Choose El Capitan, if it is available in the Updates section. It will take some time to complete the download.
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Step 5. Install the system update
Follow the directions to do this. This is quite a simple operation, which will not delete your data or settings.
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Step 6. Test the audio again
After completing the update and restarting your computer, check if the audio is working properly.