Steps to fix troubleshoot a Mac that does not have any volume:

• Check the volume; the first thing to do is make sure it hasn't been muted on purpose. To increase the volume, press the volume up (F12) key.
• Is it an issue with the app -It's possible that your Mac doesn't have sound because it won't play audio in a certain software.
• Execute the maintenance routines-If you've discovered that your Mac's sound isn't working, CleanMyMac X and its Maintenance scripts programme are worth trying.
• Make sure there are no hardware issues.-Check to see if there's anything plugged into the headphone/line out port and if it has a red light on it.
•  the most recent version of macOS installed-If your Mac still doesn't have sound, Apple recommends that you first make sure you're running the most recent version of macOS.
• If your sound is still not working, go ahead and check your Sound settings. Select System Preferences from the Apple menu. Select the Sound tab. Choose built-in speakers from the Output tab. If it isn't an option, you should contact Apple Support. Check to see whether the volume slider is set too low; if so, move it to the right and listen again. Check to see if the Mute box is checked.

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