I'm running Ubuntu 18.04.2 LTS, faced with an issue: when I connect headphones through a Type-C dongle, the system doesn't see it. Both port and headphones are working, but the headphones aren't seen by OS. Is there a way to fix it? When connected, they don't even appear in audio settings, so I'm a bit out of ideas.
I am on Kubuntu 18.04 and connected a monitor (lg-27MU88-W) over USB-C. The monitor contains a headphone jack that appears as HDMI output in Audio preferences.
Selecting Digital Stereo (HDMI) Output makes headphones work for me.