To add my experience for the benefit of others…
“The noise” has OFTEN appeared in the following conditions:
- Single drive in 1-bay QNAP NAS formatted with EXT4
- Two drives in RAID1 in 2-bay QNAP NAS formatted with EXT4
“The noise” has NEVER appeared despite many weeks of tests in:
- External SATA USB3 single drive enclosure formatted NTFS
- External hardware RAID unit with two drives in RAID1 and NTFS
The above is consistent across five different WD100EFAX-68LHPN0 drives with Firmware 83.H0A83 from retail, shucked and direct from WD via their RMA process, all of which were manufactured between February and August 2019.
So the mystery continues; the above suggests that RAID itself cannot be the cause - unless the 1-bay NAS has the same board as multi-bay models & so a RAID controller is still between it and the SATA. Or perhaps it’s EXT4 - I don’t know enough about that. I’ve also now ran out of care and suitable equipment to do more tests, and accepted “the noise” for what it is - an occasional downside of an otherwise great product. Until the disks fail in a few years and WD announce they built them with problems.
The most common occurence is after a large amount of data movement. When the NAS is just running or carrying out its various tasks, I hardly notice it’s there. Overall happy with the drives and in my opinion still the best on the market even with this issue.