Answer:
To fix above error follow below steps.
Uninstall and reinstall the Realtek audio driver by using below steps.
On your keyboard, press the Win+R (the Windows key and the R key) at the same time to open run terminal
Type devmgmt.msc and click OK to open the Device Manager.
Expand the category Sound, video and game controllers. Right-click on the Realtek Audio Driver and select Uninstall, then follow the on-screen instructions to uninstall the driver.
Restart your computer and open Device Manager again.
In Device Manager, click Action > Scan for hardware changes.
After that, install the driver again.