"Macbook Pro wont play audio on DELL S3222HN: My New Macbook M1 PRO won't play out of the speakers of my New DELL S3222HN Monitor. The options is shown in System Settings. However when I click DELL S3222HN, the volume bar and mute clickbox disable. Anyone have any Ideas? My other drivers seem to work fine."
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Thank you for the screenshot.
Troubleshoot the Mac Audio:
What to Try:
A. Unmute the App:
If an app has its own audio input and output settings, then perform things on the app itself.
B. Remove External Devices:
Verify what your output item is.
C. Disable Bluetooth:
If there are any microphones nearby, then they may be getting in the way via bluetooth.
D. Go Here: Control Access to your Microphone on Mac.
See if an app is permitted to use your microphone.
E. Reset the SMC and your NVRAM:
Sometimes when changes are made to the system(i.e. updates), system configurations (i.e. for Sound) become manipulated, technically. So, reset the SMC and NVRAM. (Applies to Anted-Based Macs Only)
F. Boot into Safe Mode:
When you boot into Safe Mode, items load by default, with certain settings and caches set aside. So, hold down the shift key upon boot. See what happens then.
G. Create a New Administrator:
See if creating and logging in as a new administrator does the trick. There may be something misconfigured in your current user - something that is getting in the way. Go to: System Preferences > Users & Groups > Unlock > Click: "+" > Create the new administrator