Thanks for your message and sorry for the troubles.
Not really sure when do you experience spin up? Generally Hard Disk Sentinel only detects the status based on the configured schedule. So if you set (for example) 12 hours, then do you experience spin up in every 12 hours (which could be normal)?
Detection of status information acts as any simple read command, causing that the idle-timer of the hard disk resets. So if the 'hard disk power down' timeout in Windows Power Management is set to higher than the Detection Frequency (on Configuration -> Advanced options page in Hard Disk Sentinel) then the hard disk may never spin down.
If you adjust these options to allow spin down, Hard Disk Sentinel detects if the drive is in sleeping mode and do not wake up the drive(s) just to update the values. Then you may see the "Power state: sleeping" instead of "Power state: active" on the Information page.
> It is a feature that has been already asked in the past,see:
Yes. This is exactly that feature: the "Automatic detection based on disk utilization".
This was required because some hard disks (more precisely the disk controller: motherboard chipset or add-on card, its driver and/or the external enclosure if used) does not provide correct power state: so even if Hard Disk Sentinel attempts to verify if the hard disk is sleeping or not - the disk drive always respond "I'm active". So Hard Disk Sentinel attempted to detect the status (which wakes up the hard disk drive).
The "Automatic detection based on disk utilization" function verifies if there was read/write activity on the disk since last access. If there was no read/write, then Hard Disk Sentinel assumes that the hard disk sleeping - so does not perform the detection, exactly to keep the hard disk sleeping.
Between the detections, Hard Disk Sentinel does not attempt to detect the status, so the disk drives should remain sleeping.
If this is not true, I'm afraid the issue may be related to the mentioned chipset, controller or its driver which may cause the troubles. You can try to update the chipset driver, as in some cases, it may help.
If you use Report menu -> Send test report to developer option, I can check the actual situation, it may give some thoughts.