Audio output device not switching to headphone on Steamdeck

When running a project build on a Steamdeck with headphones connected, the audio outputs on the speaker no matter how I tweak the settings.

The sound of the Steamdeck itself (I mean the noises when selecting buttons, etc.) does output correctly on the headphone simultaneously (I have both the headphone and the speakers producing sound at the same time).

I tried:

  • Connecting headphone using Jack cable and bluetooth → nothing changes
  • Tweaking Settings > Audio > Output → nothing changes
  • Playing in desktop mode → here it works properly but I still have to select the output device manually in the taskbar (no auto-switch)
  • Launching the game with different versions of Proton → nothing changes

Build settings: Linux target with IL2CPP backend. Everything apart from the audio output device works as expected.

Have you run into this kind of problem?
I’ve seen here that Unity only outputs to the default audio device. I cannot understand how both devices can be used at the same time.

Fixed it by simply updating Unity from 2022.3.13f1 to 2022.3.50f1
I tried both IL2CPP and Mono backends and it works in both cases.

Sorry for not trying to update before asking the question, might help people with this specific issue though.