It is expected to hear a really soft rumbling for that part of the cooling solution. Which can be heard only when being really close to the processor's socket. When you are not close to the chassis that sound would be almost imperceptible.
In the video it sounds really loud however I don't know how much as the volume augmented in order to present this behavior.
I have a Intel RTS2011LC and use it on a 4770K with the intel DZ87KLT-75K motherboard.
I have a rumbling / rattling sound that comes from the water cooler.
I have tried placing the box on its side, and the noise goes away, when I put the box upright the noise comes back.
The noise is not there all the time, it comes and goes, sometimes it is quite for 5mins before it rattles again.
When the computer is at 100% cpu usage, and the rattle starts the cpu quickly jumps in temp.
You should check that the orientation of the fan and the hosepipes is the same as illustrated on this video:
Furthermore, if the problem is randomly, it could indicate the the product is starting to fail, so you could check with your local support for a replacement on the unit.