Primary microphone not working correctly

[Hazenhart]

My primary microphone (on the bottom of the phone) is not working correctly. 
Callers can barely hear me at all. Switching to speaker mode allows others to hear me via the upper mic (if I physically block the upper mic, then I become inaudible again).  
Running the diagnostic test on the mic produces very very quiet results, even with the upper mic physically blocked, so yes the lower microphone is functioning, albeit almost too quiet to be useful. 
Safe Mode gives the same results. 
Using a third party dialer app (SimplerApps) gives the same results. 

Calling with WhatsApp gives the same result. 

BUT

When making a call with Facebook Messenger, the lower mic works fine. 
This tells me that it is not a hardware issue.  

Anybody have any ideas?  

[Martin1]

Hi @Hazenhart, I am sorry to hear about this!

Since Facebook Messenger is a third party application, I am not 100% sure on which microphone is used during calls in Facebook Messenger.

But since the Microphone test failed in Diagnostics I would suggest that you get in contact with your local support team in order to have your phone sent in to an authorized service center. If you have any questions regarding the service, such as routines, warranty and consumer laws, these type of questions are best answered by your local support team as well, as they vary between markets.

[Shabooboo]

Did you find a solution to this? I have exactly the same problem. I also did a factory reset & tried a different network SIM, same problem. 

[Martin1]

Hi @Shabooboo, sorry to hear about this.

The fact that you tried a factory reset is great and all, but since such resets only erases user data from the phone, it might not be the right thing to do here. My suggestion is to try to repair the software on the phone using a computer and Xperia Companion. By doing this, you will replace the current software in the phone with a new one. Just like the factory reset, a software repair will erase all user data from the device, so remember to do a backup before the repair in order to prevent data loss.

If the behaviour persists after the repair, I am afraid that the only thing left to do is to get in contact with your local support team in order to have your phone sent to an authorized service center to be examined and possibly repaired.If you have any questions regarding the service such as routines, warranty and consumer laws, these kind of questions are best answered by your local support team as well. 

I hope that helped! 

[mmatrosov]

I have exactly the same problem. And I did not have this problem several months ago. It all started after the most recent OS update. Seems like it introduced a bug. Hence, it might be fixed via another update. Are you working on it?