Thumping sound every 5 secs (approx)

I just bought a 6TB HGST 3.5" Internal hard drive. I inserted the drive to my newly bought QNAP NAS.
Since the very beginning, there is this annoying thumping noise every approximately 5 seconds.
I wonder is this a defective unit or normal for an HDD of this size to have this kind of sound??

I phoned my friend who also happen to have a similarly sized hard drive inside his NAS unit (different brand & model) and he said to me that he does not have this problem at all.

Hi sbrunei ,

It seems that the drive is defective. For a better assistance and to know more about the issue, you should try contacting WD’s Technical Support about this.

To Contact WD for Technical Support