Getting a weird sound/noise with haptic feedback

I’ve been using my iPhone X for a while now and yesterday I thought I heard some weird clack coming under the phone while I was rapidly scrolling up and down with the timer. Today I heard the same weird noise again but this time it was while “closing” the accessibility reachability shortcut. Did anyone else experience this?

It happens on silent (apparently it doesn’t happen on silent and probably because there is no feedback when doing it on silent) and ring and it happens regardless of the alert volume and media volume.

Edit: it didn’t happen when I was trying to record my screen with mic enabled to show what I was trying to say. It probably is related to Taptic Engine. It isn’t consistent either, sometimes it is barely hearable, sometimes it really clacks like something is pushing the speakers really quickly. There isn’t any sound when I try the vibration settings or in anywhere else really.

Edit 2: for anyone who was wondering look to this comment.