Any Media (video or music) won't play on my MacBook Pro 16 m1 if I'm using internal speakers

It is usually quicker to create a new macOS user account than it is to install macOS. Just make sure to follow the same caveats with the new user account.

Each option tends to have advantages & disadvantages. Installing macOS into a new APFS with those caveats does allow the user to forego Safe Mode & testing another user account all at once in order to better confirm if there is a hardware or software issue. However, Safe Mode & another user account can help narrow down where the problem is at if it is a software or configuration issue. It all depends on the goal the person wants to achieve first. While installing macOS to a new APFS volume is like a clean install, it is not because you are still using the same file system & the same hidden system boot files & same security enclave chip data.

Now with the 2018+ Macs, and especially with the Apple Silicon Macs even a clean install to an external SSD is not without some drawbacks either. You would think a clean install would be a perfect test to determine a hardware or software issue. However, with the security enclave chip controlling security & privacy, many times that security enclave chip is the problem. A DFU firmware Revive can correct some security enclave chip issues, but if the issue is due to corrupted user information data in the security enclave chip, then performing a clean install to the internal drive may be the only way to resolve the issue (best to do a DFU firmware Restore on an Apple Silicon Mac as it resets the security enclave, system firmware & pushes a clean OS onto the internal SSD).

Even installing macOS to a new APFS volume won't help if the data in the security enclave chip has a problem or if some of the hidden partitions/Containers has some sort of issue. With an Apple Silicon Mac, the Mac will always need to boot from hidden boot code located on the internal SSD even when booting from an external drive. Apple recently had a bug with macOS Ventura where the system firmware was updated with a Ventura update patch which installed system firmware for Sonoma. This Sonoma firmware was incompatible with the older Ventura boot files located in a hidden area of the internal SSD and it prevented Ventura from booting after the Ventura update patch. (I personally encountered both bugs -- second bug I resolved through the clearing the NRAM).

Troubleshooting is getting much harder these days. Testing with a DFU firmware Restore is about the only real way to confirm a hardware or software issue, but you still have to consider the possibility of an unconfirmed new bug.

Just to clarify Room101A's reply....

Apple Silicon Macs don't the ability to reset those. The only thing I've read that sometimes works is to reset the SMC by powering off the Mac for at least 30 seconds, then powering it back on.

The above being said, sometimes restarting your Mac in Safe Mode clears up weird anomolies like this. Start up your Mac in safe mode - Apple Support

You can try creating a new macOS user account. Log out of the main user account. Log into the new macOS user account to see if you have the same issue. If the new user account works, then you have a configuration issue with your main user account (or a Login Item may be causing a problem).

Have you tried booting into Safe Mode to see how it works?

You can also try installing macOS to an external USB3 SSD and boot from the external SSD to see how your audio behaves. I guess if you have enough Free storage space on the internal SSD you could create a new APFS volume and install macOS to it (just make sure to give it a unique name....maybe "macOS Test"). Do not install any third party software. Do not restore from a backup. Do not log into your AppleID or iCloud (this is very critical when troubleshooting). If this works, then you know you have some sort of software or settings issue with the internal boot drive. Reinstalling macOS over top of itself doesn't do much these days due to the sealed system volume.

You can use the command line to clear the NVRAM (both Intel & Apple Silicon Macs.....just don't configure any specialized settings for the NVRAM or it may prevent an Apple Silicon Mac from booting since most Intel settings are not compatible). Launch the Terminal app & issue the following command:

sudo  nvram  -c

This will prompt you for your macOS admin password. Nothing will appear on the screen as you type the password. Press the "Return" key to submit the password.

You may see a message that certain settings cannot be cleared (usually associated with the computer's name). As long as there are no other errors saying the command failed.....reboot the computer so that the system loads the default NVRAM (aka PRAM) settings. You will need to re-select the default Startup Disk in System Settings.

Unless you have some third party software installed which can affect the audio processing of macOS or you have external speakers/headphones connected (or anything plugged into the headphone jack of the laptop), then you can try a DFU firmware "Revive" which resets the security enclave and system firmware.

How to revive or restore Mac firmware - Apple Support

Revive or restore a Mac with Apple silicon using Apple Configurator - Apple Support

Your suggestion that the OP could create a new APFS volume and install macOS to it is one I had never before considered.

In general, if one has the room and follows all the caveats you stated, do you think this is a better method of troubleshooting a problem like the one the OP is experiencing than would be creating a new User account in Users & Groups and switching to that account to see if the problem persists?

Sound like you have a serious problem if a restart won't fix it. May I suggest you google for how to zap the PRAM , NVRAM, and SMC for your specific computer.

Doing so certainly won't hurt anything and it may just fix your problem.

1. Try to go to "setting"
2. select "sound" in setting
3. In section " Input and Output " choose macbook speaker.
4. Then test again.

Hope it works

I have to restart each time I lose sound from the internal speakers on 2020 iMac, SSD, macOS 14.3

Wow. Just wow! Terrific reply and thanks for taking the time to write it. Learned a lot from it.

The next time it happens take a look at your Bluetooth settings.

Is it possible the Mac is trying to stream your music to a connected Bluetooth device?

That's great advice, something I have to remember myself.