Hi - I had this problem - my ASUS mb which used driver 6.0.1.7553 and 2004 update broke it.
The latest update for my mb is 6.0.1.7848 (still an old version from 2016), but installing that did not resolve it.
What fixed mine was to disable all audio drivers - then in device manager -> Action menu -> select 'Add Legacy hardware' - then choose the option to 'install the hardware that I manually select'
Under Sound Video and Game controllers select Realtek and you should see the Realtek High Definition Audio name - select that and tell it to install it.
Windows will do this and then complain that it does not work. Try using Media Player to check that it is not working.
Now go back to device manager and disable the new entry and re-enable the earlier installation - and for me it now all worked .... the final device manager looks like this - both Realtek options are for the same driver version but now the first one works !
It seems that when Win10 tries to install the Realtek driver it does something that the Realtek install does not do ... and having done that the original Realtek install will then work ...
MS needs to get its act in order - the great thing about windows is the hardware flexibility but they seem to squabble with the manufacturers over trivia....
Just noticed the other thread :
suggests that triggering a manual update of the initial Realtek installation might also work - I am not going to touch mine again now that it's working but that is also probably worth a try (see Wh0Carez reply)