Generally Ubuntu and derivatives are really good at detecting your hardware. Just my bad luck that the 18.10 release didn’t like my Xonar DG soundcard and my machine produced no sound at all. Frustrating as this all worked with 18.04 🙁

Well, time to open the terminal and launch Alsamixer:

alsamixer

I played around a bit with the settings until I got sound again, then quit and saved the settings with the following command:

sudo alsactl store