Perhaps my similar issue is not related to Asus, but Gigabyte and Ultimately REALTEK.
Nevertheless it is a REALTEK issue and here is my "work around" since MS hasn't responded to my opened ticket.
......I decided (per Gigabyte's suggestion/explanation) to do a clean install (again) but this time was to 1909 built and the sound WAS back, using a MS driver (great), As a test (and again as suggested by Gigabyte) I installed the 6.0.8854.1 and it BROKE, well WE knew that.
Test #2, I place the MS driver back and upgraded to Win2004 built, sound STILL works.
Test #3, upgraded the driver now to the 2004 built 6.0.8945 and it BROKE, so revert back to MS driver.
I doubt that this is going to get resolved properly, MS (rightfully so) says Win10 works as designed. and Gigabyte refuses to even acknowledge ALL the posts EVERYWHERE, because the have test results on file showing that Realtek drivers work...on a clean install....
So, my suggestion is...if you are not running a recording Studio and just want t have some sound.....keep the MS driver.
Good luck.