Solved Volume (output or input) keeps going back to 0 when trying to increase it

A few days ago, after starting up my laptop as always, Windows couldn't detect speakers and said "No audio device installed".
After quite a lot of researching and trying stuff I found the problem - the service "Windows Audio" was not running. So I tried to start running it, but got an error. So I kinda fixed it by following this guide: How to Fix Windows Audio Service Error 0x80070005 (AudioSrv)
Now it doesn't say "No audio device installed" anymore and the speakers are now detected by Windows again, but I can't increase the volume because the volume bar in the "Windows quick menu" snaps back to 0 when trying to increase it. The media control keyboard button doesn't increase it either and in the "More sound settings" in the settings under System > Sound in the section "Advanced" under the Levels tab, there's just nothing.

I really don't know what to do anymore and can't find any solution to this problem,
so if you have any idea of how I could solve this, I'd really appreciate your help.
Thank you!

Did you try: System> Troubleshoot> Other Troubleshooters "Run Audio" test

Take a look at your "Device Manager"

Check Application Settings
Volume Mixer Settings
Driver Issues
Hardware Issues
Check for Background Applications

you might have to modify a file, folder, registry key, wait for some more posts........

It might well be worth restoring your last good system image.
Or perhaps Lenovo support provides an audio driver you could reinstall.


Denis