I have the problem when I go with my Bluetooth headphones in a call while listening to music or similar media on the phone, the sound quality is very bad, but where these are normal but outside the call as usual.
Mobile: Huawei Mate 20 Pro
Headphones JBL TUNE 160BT
That is normal. The manufacturer intends that you can understand yours. Already had that with a mobile phone.
Can't somehow get rid of this suppressed "mode"? So I mean that's a bit annoying.
Unfortunately, I do not know
If you hear music at the same time as the call, our brain has a harder time filtering out the caller's language from the noise mix.
That's why you have trouble understanding the radio on the highway with normal speakers if you're not very loud.