Can hear sound of button tap when shaking my phone

[TheGoodNamesAreGone]

I noticed my phone was making some strange noises in my hand. I shook it and it makes sounds like a button is being tapped. Strange.

 

[N4Newbie]

Not sure what you are hearing but one thing that throws most people is the realization that your phone's rear-facing camera has a mechanical focusing mechanism and, yes, it will rattle somewhat if shaken.

Know Your Smartphone: A Guide to Camera Hardware - TechSpot