Make sure you check whether this is the cause of your problem! This is quite a big mistake by Microsoft as hiding the device under Recording devices was definitely unnecessary. It might be considered unnecessary or might have been disabled by a third-party app. It’s quite possible that Windows 10 has somehow automatically disabled the Stereo Mix feature as a virtual sound device.

Restart your computer in order to see whether the problem still appears!.

Switch the slider next to the apps you wish to provide access for on the list to on.

After that, switch the slider under the “ Allow apps to access your microphone” option to On and scroll down in the list of installed apps on your computer.

If it’s not, click on Change and set the slider to on.

First of all, check if the Microphone access for this device option is on.

Scroll down until you reach Microphone and click on this option. At the left side of the window, you should see the App permissions section.

Scroll down until you see the Privacy section and make sure you click on it.

Click the cog icon in the lower-left section of the Start menu to open the Settings app.

This solution is the simplest and it can save you hours of effort so make sure you don’t skip this method when troubleshooting the Stereo Mix missing problem on Windows 10. This automatically disables the use of Stereo Mix. This problem can also appear if your microphone is not available for access. Solution 1: Make Sure Your Microphone is Available for Access

Audio driver – Stereo Mix is only available for drivers provided by your manufacturer and you will have to update them if you are using the default ones made by Microsoft.

Stereo Mix is simply listed as disabled – Stereo Mix may simply be disabled as a virtual audio device in Sounds settings so make sure you simply re-enable it to resolve the problem.

You need to allow apps to access your Microphone in Windows 10 Settings.

The microphone is inaccessible – If your microphone device is not accessible for audio recording, Stereo Mix will be disabled as well.

How to use audio mixer