(iPhone 6S+) Clicking sound embedded in videos when I record them

[wallmaxx]

Newish iPhone 6S+ two months old.

Noticed clicking when I recorded my dog chasing a toy using Slo-mo on 720 @ 240 fps.

This is the first time I noticed this. Has anyone run into this before.

 

[evamoree]

Can you give more info? How many times does the clicking sound happen per video? Are you sure its not an external noise? slo-mo does pick up and magnify even the tiniest of noises