No auto sleep, usb HDD, Roon Core

Hi.
I’ ve just set up my Roon ROCK in a headless Intel i7 System, connected my library via external usb 3.0 2TB ToshibaHDD.
Everything runs perfect. But the HDD is Always Spinning, can auto-sleep be activated?
The ToshibaHDD was formerly in a Setup with an Auralic Aries Streamer and Auto-Sleep worked quite well.
The Library Scanning Procedure was completed 24 hours ago!

System Status
Serial #0001C00E02A7

Operating System
Reinstall
OK
Version 1.0 (build 150) stable
Running 21 hours, 48 minutes, 30 seconds.
Roon Server Software
RestartToggle Dropdown
OK
Version 1.3 (build 276) stable
Running 21 hours, 48 minutes, 20 seconds.
Roon Database & Settings
Reset
OK
95% of 55 GB available.
Networking

There is a library scan and then there is Audio Analysis which can take days depending upon your library. To see if Audio Analysis is still going on go to settings/library. Near Audio Analysis speed there will be a track counter if it is still processing.