Echo issues while on phone call

[Ann9]

Hiii.. It's been over a month when I upgraded my Z5 that when I speak on the phone I hear the other person like it's on Loud speaker and have echo issues. I send my device for service to an authorised Sony store and they told me there is nothing wrong with my device.. How can i fix this!?! 

[MarlonUk1]

did you showed the problem to the tech in the service center?

try to change mic sensitivity on the sound settings

[Ann9]

Yes I stated the specific problem and they didn't find anything. And I also adjust the mic sensitivity but still the same issue

[MarlonUk1]

I meant , did you demonstrated to the service center how the problem works, like make a call right there and let the technicial hear the echos.

does this happen when you are using headphones?

 how about when you are on safe mode

[Ann9]

Yes we made several calls while I was at service to show them exactly how you hear the one you are talking too and it was very clear to them what the issue was