Camera ring/lense making popping noise?

[opticflare]

Hey all, using my 2014 Moto X was just taking a moment to clean the case / camera lens with a cloth and I noticed when I ran the cloth over the camera lense and flash ring it makes a very light popping sound.. Especially when rubbing side to side or up and down in a cross fashion. Still seems to take good pics, just wondering if others Moto X is doing this, it seems okay but I haven't heard it before.

Try taking a moment to wipe your camera lense, do you hewr any light popping or any noise?