I recently installed Linux Mint, version 21, on a Dell XPS-13 9360 laptop to use as my spare laptop. However, the microphone doesn't work, as I learned recently when I tried to use the laptop for a Zoom conference and nobody could understand me. I then installed Sound Recorder to test it, and all of the recordings were garbled and full of static. Interestingly, this laptop previously had Windows on it, and there was no problem with the microphone under Windows, as I know because I did plenty of Zoom calls with it back then. So, it's probably some sort of driver issue.

I ran the command "lspci" to try to figure out what model the microphone is. One of the lines of output was "Audio device: Intel Corporation Sunrise Point-LP PMC HD Audio (rev 21)." This was the only thing that looked like it might relate to the microphone.

However, I don't know where to go next. I looked up this model of laptop on Dell's website, and they have Ubuntu drivers for some things (mostly BIOS-related), but not for the microphone. I dug around online to try to find more about the "Sunrise Point-LP PMC HD Audio" and learned that some Linux users have apparently had microphone problems with it, but I didn't see any clear solution.

Any suggestions anyone has would be greatly appreciated. I'd like to get the internal microphone working. If I can't, then I guess I could buy an external USB or bluetooth microphone as a last resort, especially since this is only a spare laptop for when my main laptop is either not working or not with me, but I'm not even sure if using an external microphone would solve the problem.

Most laptops I have looked at, the mic is part of the sound system and are attached to the USB bus, not the PCI bus.

Look at lsusb, you should see the camera. The mic is just a reverse speaker. So, you need to look at your sound system to get any clews on what might be wrong. If you have the correct drivers loaded and can play sound, it is eathier a hardware failure, or things are not adjusted correctly to produce sound.

I would assume Mint uses Pulse. If you are using Pulse, open up Pulse Audio Volume Control. Click on the Input tab. From here you can mute, or unmute the mic, adjust the volume etc.

On my Acer I have a radio stream playing, the mic is not muted, and a resonable volume is adjusted. I can see the indicator bar bouncing back and forth to the music.

Have a look there and tell us what you see.

If you have access to an external mike and the machine has an audio jack, you might want to test with that, just to rule out a hardware issue with the built-in.