There is no sound on ubuntu 22.04 and 23.04. Bt headphones play sound. I would like to receive an official decision from Chuwi representatives
Up until three days ago (March 3), the daily pre-release version of ubuntu 23.04 was still using kernel version 5.9, and therefore sound still did not work. The version of March 5 uses kernel 6.1, and sound now works. It is necessary to invoke alsamixer (in a terminal), and after counting the 43 (!) possible adjustments this sound card has, you need to modify 5 of them: the headphone, headphone mixer, and DAC sliders all should be raised to maximum, and right headphone mixer and left headphone mixer (way to the right in alsamixer) should be unmuted by pressing ‘M’. The volume can be adjusted with the usual ubuntu sound control in the upper panel. Both the speakers and the headphone jack work, and switching back and forth is done just by plugging/unplugging the headphone plug. The speaker mute control in alsamixer does nothing. Volume is adequate for both, something I noticed was not so when I tried Manjaro and EndeavorOS, which do have the 6.1 kernel, but weak sound output.
One other factoid - the cheapo USB-to-analog heaphone dongle I bought on amazon the other day, which works fine on my Samsung phone, but does not work with ubuntu mate 22.10 (it stutters and freezes other processes on the computer), does in fact work properly with this ubuntu 23.04. Mate 22.10 does work with a CM106 type D/A dongle, so it looks like something got added or fixed.