My Samsung note 4 (n910v) mic is not working.

A

AC Question

To start off I've never had an issue with the phone and never been wet or damaged, it started when I cracked my rear camera lense, tore down my phone to replace the actual camera and glass cover, upon doing this I accidently cut the fiber cord for the (recent apps) sensor button. So I ordered a USB charging port for my exact phone model (n910v TR-2). The whole week waiting the phones mic still worked.
Received new USB port in mail, replaced it with damaged one on phone. Started phone up ran through its paces and everything works great except people can't hear me when I'm on phone with them, OK Google won't recognize me, nothing works on lower mic. If I put phone on speaker they can hear me fine.
Things I tried were cleaning mic holes, talking to voice recorder and calling people again nothing works. If I yell at phone while it's recording you can barely hear it on playback even with media volume all the way up.
So I ordered another USB port from different vendor and same thing! It doesn't work!
I put the very original one from factory in (with damaged recent apps button) and mic works perfect... any help is appreciated.