I forgot to state that after the 10 issue, I had then taken it upstairs to connect to the 7 system, which worked with it fine. No switch off or spin down in 7, only in 10. I no longer have 8.1 to test.
I normally use HDDSpin to spin down my external drive when it is not being read or written to, rather than simply removing any cable, avoiding that clicking sound of a drive stopped suddenly. Thanks