I had the same problem and after 2 hours of trying to pinpoint the cause, I've found out that the Recycle Bin plugin was the culprit! I had to turn this setting "Update Recycle Bin Size in Background?" to No. "...and prevent disk spinups when accessing the Recycle Bin." – Ironically this just spun up my disks every 5 minutes and as I had the delay for spin down set to 15 minutes, they never spun down again except if I did it manually. But then after some minutes they spun up again because of this setting. ☹️ Just thought I'll share. Maybe this helps someone else who had this issue but it wasn't connected to the rclone issue, that @ghighlie found out... ✌