Hi @mdduan. Based on the information you gave. There is no problem using the 3rd party application, that's why there is no problem with the mic or mouthpiece hardware.
Now the reason why we advise you to go to our service center is so our technician can check your phone directly. As you can see not all user got this problem. If this really a bug from our update we will surely fix this but now we need to check your phone first.