Do you have this Z170-A | Motherboards | ASUS USA ?
No, an ASUS Prime Z390A. Actually, I read elsewhere that some were having a lot of problems getting the Realtek drivers now, so I'm gonna stick w/Microsoft's driver for the time being.
I don't know whether it's because Full telemetry is enabled on here or something else unknown but the sound issue is, for the present time, sorted. If it pops up again, I'll try what was suggested elsewhere: use Display Driver Uninstaller in safe mode, restart, and let Windows reinstall the sound drivers. They're fairly recent--5/2020, according to Device Manager. Haven't tried this method yet, but hopefully it works on Microsoft drivers and removes them. Has anyone tried this yet?