19043.985 was the base release of 21H1. You mentioned that you had separately updated to 19043.1023. That is KB5003214 which was a "preview" update. Microsoft sends these "preview" updates out usually in the final week of the month. They are usually flagged as 'optional" updates, but it seems some people get them regardless. I don't know if it actually has a "preview" moniker associated with it once you install it, but if you installed it separately, it should be listed separately in your updates. If you installed 21H1 from the Media Creation Tool and it already contains it, then that KB would not show up. The second Tuesday of the following month is when Microsoft releases the "final" version of these updates. If you could back out KB5003214, then you would be back to 19043.985. Here is more information on KB5003214: https://www.tenforums.com/windows-10-news/179986-kb5003214-windows-10-2004-19041-1023-20h2-19042-1023-21h1-19043-1023-a.html
I don't see any sound issue complaints there. Most people complaining about Taskbar issues and the new "News and Interest" icon on the taskbar.
Good luck. I hope you can get your problem resolved.
JohnD