WD Red Pro Drive making a strange "beeping" sound


I have just received 4x Red Pro 8TB Drives for use in my Synology DS918+ NAS.

When reading a Time Machine backup onto my Mac from the NAS drives, halfway through the backup process, one or more of the drives started to make a very strange “beeping” sound. I don’t believe it was beeping per se, but it sounded like the HDD drive head was stuck and potentially damaging the rotating disc. It made this noise many times each minute, for a couple of hours, and then stopped. Since then, I have not heard it make the noise.

I am concerned that one or more of the drives are defect and/or damaged by this. I don’t know which drive might have been the problem.

Please see this video, where the sound is through-out, but particularly after 00:30:

Is this a problem you recognize? What should I do about it?

It is recommended to check the health of WD Red drives by connecting them in computer using WD Data Lifeguard Diagnostic Tool. You can run Quick Test and Complete Drive Test to check the complete health of WD’s internal hard drives.
If fails, would be better to replace before taking the backup of important data files.

I have the same problem too. How did you resolve the problem?
Synology said it’s not NAS problem, but hard disk issue.
Western Digital said no problem at the first time and later getting RMA.

I tried several hard disk tests with Western Digital DLGDIAG, HD Tune Pro, and HD Sentinal.
Unfortunately I didn’t find any error messages.

If I remember correctly, WD also said first that it was a problem with the NAS, but later agreed to RMA. I’ve since used the replacement drives in the NAS without this issue, so I am pretty sure one or more disks were problematic.