Mobile camera clicks when starting?

I've had an iPhone 8 Plus since September 2017 and today I've noticed that this rubber ring on the back of the phone, which protects the phone from entering from the water, is slightly loose.

I pressed the ring a bit and knocked on the camera to hear if water had entered (I know, stupid)

when I wanted to test the camera if there's anything (theoretically good) I heard when starting the camera app a click from the camera

such a sound makes the "destroyed" Huawei P8 lite (2016 Ca.) also

what is going on and what can you do?

I mean I could not care, because the photos still look good (is that probably the optical image stabilization?)

I also wanted to ask who has such a problem as me

Go to an Apple Store and ask

As moving parts, both lenses have the zoom and the main camera still the optical image stabilization.

Both could trigger it.

Both works as usual

It could be that they are not running, because this sound "unhealthy Kling" after I knocked "a few times" on the camera

As long as it works, I would not necessarily do something.