Curious about the noise the Taptic Engine should make when pressing the Home button on the iPhone 7. When I press it I do hear a dull noise that sounds a bit like a spring. Only noticed it today when in a quiet room. I understand the Tapic Engine has a spring or multiple springs so this seems to be normal but just curious what others hear. Mine doesn't have any rattling noises - just a dull noise. Curious how durable this will be long term?