Having issues with iOS HFP BC127

So I’m having a problem with calls in iOS systems. During a call there’s a lot of noise but the call signal is still passing through since you can hear the other person even though it’s very low sound.
This doesn’t happen if it’s two android calling each other, there’s no noise in the channel. And if a iOS calls an android, still no noise, but if android calls iOS there’s the same noise as iOS calling iOS.
Do you have any idea what might be the problem?

So I solved part of the problem when I upgraded from 7.2 to 7.3 firmware, but I still have a problem that the person on the other end hears noise whenever they talk, anyone have this problem?