[SOLVED] Echoing sound during call (Global rom)

[r.omega888]

I have recently bought a mi note 3 and it has a strange echoing sound during call. The problem is only present during normal call (without earbuds). It seems like the top mic is not turned off during the call and it picks up the sound.

I have tried the following things:
- Reboot
- Factory reset
- Different sim cards
- Turning on off mobil internet
- Calling different persons
- Lowering the call volume
- Calling from third party app

None of this worked. The issue is present during every phone call. No matter where I am or who I call.

Miui version: 10.2.2.0 OCHMIXM Global
Kernel version: 4.4.78

As a last resort I am thinking about rolling back. Do you have any other ideas?

 

[r.omega888]

Rooting my phone and changing the following in the build props solved the problem.

persist.audio.speaker.dualmode = false
ro.vendor.audio.sdk.fluencetype = none