Bug where minor sounds randomly disappear.
Same issue here:
steamcommunity.com
forum.paradoxplaza.com
Is there any fix?
Same issue here:

Sound bug? :: Crusader Kings II General Discussions
Something of an audio issue I've been having recently, across both vanilla and my mods. The games sound-effects (clicking on provinces, events, pausing, exiting notifcaitons, etc. etc.) keep going in and out randomly. One minute you can click a bunch a provinces and you'll hear the tap tap that...

Sounds constantly disappearing
I have this strange annoying 'bug' where the game sound constantly drops out, comes back for a few seconds, and disappears again. This does not affect the music, but the 'clicking' sounds that should be made when you click on news features...
Is there any fix?