Mi note pro low volume in call (in ear speaker)

Hi guys I've got a very annoying problem, the volume of the internal speaker, it's very low. When I call someone it's very difficult to understand what the people I'm calling says.

I'm using MIUI 8 weekly ( our last release for our phone)
The phone is unlocked trough the official unlock software.

Any suggests will be appreciated!

Cheers

from xda-developers http://ift.tt/2af1q95
via IFTTT