This is happening for me as well. Interestingly, I have 2 micro servers both configured (almost) the same way - but their hardware is slightly different - 1 x HP N54L and 1 x HP N36L. The drives on the N36L never spin up unless a genuine access request is made. The N54L drives spin up every 30 mins or 60 mins, depending on, well, who knows....it's that weird. This has been happening for the last few releases. I'm going to do some booting into safe mode and see if the issue remains. I'm also going to check that the bios options are the same for each. Diags attached if it helps....
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