Recently I've noticed that whenever I record anything that uses phone's microphone, it will always record it with this annoying tapping sound on the background. It kind of resembles mechanical watch clicking. I've been using my phone since it launched and turns out it's been there this whole time. I just never noticed it because other sounds always overshadowed it.
You can hear it in attached video.
I don't think it can be fixed.
Be wary and check it whenever you buy yourself a phone.