This question is very similar to SMPlayer has no sound with any output driver, but no solution from there is working. Also I have more recent versions:
mpv 0.28.0 and
mpv alone is working, but there is no sound for every single output options in
smplayer. I don't even see the application in
pavucontrol, it seems like the audio is diabled in SMPlayer somehow, or incompatible with some mpv option. VLC and MPV players are working fine (sound is present, can be redirected to any device in pavucontrol tool).
Any idea how to fix this or how to downgrade to previous package versions which were working (at least the sound, now it is totally unusable)?