It says no audio device is installed when I plug in my c920 logitech camera

I found a solution to my Logitech Webcam on Elitedesk 800 G9. Same problem with Logitech Webcam C925-e, Windows 11, when connected, it disable my Sounds.

Before connecting Logitech Webcam, install LogiTune from Logitech, then test/update Realtek drivers properly. Connect Webcam, go to Sound Mixer, set everything to Realtek as default, Except Input device Microphone has to be set to Microphone (Logitech Webcam). Also under LogiTune in Sound Mixer, set the input device to Microphone (Logitech Webcam...). As long as this setting maintain, system is stable, Team or Zoom meeting works properly, no more freezes and sound issues. Good Luck.

Same problem for me with the same laptop and recent updates

We have experienced an issue with a recent Windows 11 update that causes the Windows Audio service to stop whenever a Logitech C920 webcam is plugged in. Restarting the audio service is temporary and it stops again as long as the C920 webcam is plugged in. Unplugging the C920 webcam allows the audio service to remain on when it is restarted.We have experienced this issue on multiple models of HP laptops, but not on our Dell laptops and workstations. Replacing other components including docking stations, soundbars, etc make no difference. Replacing the Logitech C920 with a different brand resolves the issue, so it is specific to the Logitech C920 and a recent Windows11 update.

C920 causes issues as described, a C270 worked ok

I forced the C920 driver(Microsoft) under "Sound Video & game controllers" to use the C270 driver (Logitech)

leaving camera as C920, seems to work, whether microphone is performing as well as it could i don't know.

just waiting for Microsoft or Logitech to fix properly.

Only works until reboot, then have to reload "wrong" driver then start "Windows Audio" service