Latest windows update stole some of my system sounds, as well as toggle keys. It also made headphone audio behave very loud and compressed, added slight reverb and only goes back to normal after unplugging and reconnecting headphones.
The update did not touch audio, no Realtek driver was updated, but it's windows, so...

Another update on the same laptop, sounds all back, audio no longer annoyingly compromised... No, I don't get it either but I'll take it.