Reinstall audio drivers:
Open Device Manager
Expand Sound, video and game controllers
Right-click Realtek Audio → Uninstall device along with "Delete driver software"
Restart — Windows will reinstall the driver automatically
Update via Surface app — Open the Surface app → Check for updates → Install any firmware or driver updates pending.
Run Audio Troubleshooter — Settings > System > Sound > Troubleshoot
Restart the Windows Audio service — Press Win+R, type services.msc, find Windows Audio, right-click → Restart.