My Passport won’t stop after unmounting


I have a new WD My Passport 4 TB. Connected to a Mac, with two partitions - one APFS and another for Time Machine. I encrypted the drive (on hardware level) using the WD tool, the APFS partition is not encrypted, only the whole drive is hardware encrypted.

When I unmount this drive to physically remove it, the drive is still rotating. The disk rotation can be heard and the led is still blinking. If I remove the drive then, it makes a strange sound and the disk sound can be heard for some seconds after disconnecting. Probably caused by the motor lost power suddenly.

I have an older My Elements 2TB that is NTFS formatted and that I use for Windows. When I unmount that one in Windows, and even in Mac, after ejecting/unmounting you can immediatey feel that the disk stops and it feels safe to remove it. That’s what I call expected behavior. But I feel that by removing the new My Passport while still rotating might get it damaged. I googled about this but didn’t really find a solution…

What I get from this is as follows: You have created one partition for Time Machine; could be possible that when you try to eject the disk the Mac is taking time machine backup on your partition. The process is running and removing the disk between the process may cause abrupt noises. Usually, a dedicated external drive should be preferred for Time Machine storage device.

It’s my assumption only; the problem could be something else as well. Have you tried running Disk Utility First Aid?