iPhone 12 Microphone Issues

Hi ckgkssk,

The support page If the microphones on your iPhone aren't working offers these steps you can and may have already tried in isolating microphone problems:

"If you want to try more steps on your own

If you prefer, here are some more steps you can try on your own. You might still need to contact Apple Support after following these steps.

If people can't hear you on phone or FaceTime calls

1. Open the Voice Memos app. 
2. Tap the Record button , speak at the bottom of your phone, then stop the recording. 
3. When you play back the memo, you should hear your voice clearly.

If people can't hear you when you're using speakerphone 

1. Open the Camera app.
2. Record a video while speaking at the top of your iPhone.
3. Tap the camera chooser  to switch to the other camera. Then record another video while speaking at the top of your iPhone.
4. When you play back the videos, you should hear your voice clearly.

If the microphone doesn't work in a specific app

1. Go to Settings > Privacy > Microphone.
2. Make sure that the app is enabled.
3. If the app has permission to access your microphone, or if it isn't listed, contact the app developer."

Note that these are methods of isolating which of the several microphones may be experiencing a problem and in themselves would not be expected to correct any issues. Contacting Apple using the provided links would be the next step if cleaning the microphone areas does not help.

Regards.