Volume is too loud when using JBL headphones

I bought JBL wireless earphones and the volume is way too loud on the lowest setting.

I contacted Apple Support and I got the advice to use the dB setting. It helps only a little bit but the volume is still too loud.

I contacted JBL and they replied that they can’t do anything about it.

I have sensitive hearing.

I believe this has something to do with the connection between iOS and third part wireless earphones?

(Using regular earphones with the Lightning adapter works fine.)