Microphone not working on any apps og calls

Suddenly my iPhone 5s microphone stopped working, i can't record video with sound and people can't hear me during calls unless i have them on speaker.

It might have happened when i replaced the battery but i'm not sure.

I tried replacing the mic - same problem. When i tried the in an other 5s it worked fine. I've checked and it doesn't look like the motherboard is missing anything near the battery connector or the connectors around it.

Does anybody know how to fix this?