BG2 (baldur's gate 2) sound is mono

I have BG2EE from GOG, v2.6.6.0, newest Kubuntu 25.04, (previouslu Kubuntu 24.10), it works
however music/sounds is mono :confused: (and it’s stereo under Win11).
How to fix it ?

I think once I heard in stereo, but now I’m not sure…

https://paste.ubuntu.com/p/Cj9TbqVk2x/

other games have stereo sound.