I installed Ubuntu-Mate on a Raspberry Pi, since I am using it for robotic stuff and needed extra resources so I disabled lightdm (which improved performance a lot) with
sudo systemctl disable lightdm. Since then I can't reproduce sounds with it (which I need). Not even
If I start lightdm again, sound works again. However performance drops down.
I am almost sure ether lightdm or mate (which is started by lightdm) do something with ether alsa or pulseaudio, I just have no idea what.
the user is already on