Here are a few things that could be causing the issue.
Contents
Ensure Volume/Ringer is Turned Up
check that the volume/ringer is turned all the way up.
Ensure that your finger or case is not accidentally covering the microphone hole while you are recording.
Also, clean out the microphone jack using compressed air or a toothpick if needed.
A needle seems to work for cleaning them out.
Airplay is On
Ensure Airplay is not enabling a connection to another unit.
