Mybook 4TB frequently working hard

I have had a mybook 4TB for at least a year, maybe two years. I use it as a drag-and-drop manual backup for my iMac. I did not install any of the WD software, and I don’t use it as a Time Machine drive.

It works fine, but I’ve noticed in the last several months it makes a lot of noise as if it is searching for something, even when it’s not in use. it’s the same regular noise I hear when I am opening a folder and files. There’s no clicking or odd sounds. It will go like this for maybe 20 minutes then stop for a while then start up again, whether I am at the computer or away from it.

This stops when I unmount (eject) the drive from the desktop.

I am not seeing any problems or failures, but I can’t believe this is good for the drive.

I checked it with Disk Utility which told me there was nothing wrong after some analysis.

Any ideas on what is happening, and what I might do to fix this?

iMac Retina late 2015
OS 10.14 Mojave
WD drive is ExFAT

Thanks in advance for any ideas or suggestions

Hello calden,

You can refer below article to check whether the drive sounds normal or not: