Galaxy S10+ - beyond2lte - low volume in calls

I recently got an used Samsung Galaxy S10+ (SM-G975F) and installed /e/ om it following noe of the good guides in this forum.
Thanks to all contributors.

The one thing I struggle with is low volume in internal speakerphone during calls. I see some others also have similar issues. Even with volume slider on full it is difficult to hear.
In Lineage forums it is mentioned to modify some Mixer setting files, will this help for this rom also? I have not been able to locate these files om my phone.

All suggestions are most welcome.

Installed rom: 1.17-s-20231111351092-dev-beyond2lte