I have two external drives connected to my Mac Mini running 10.10. One is a Lacie d2, connected via Firewire; the other is a Seagate Expansion, connected via USB3. If I boot up the Seagate drive, the Lacie spins up, too. It doesn't mount to the desktop, but I can hear it spinning. When the Lacie runs automatically at night for backup duties, and is automatically ejected, it continues to spin and make the spinning noise. The noise is annoying, and in both instances I have to manually eject the drive to stop the spinning noise. Can I stop it doing this? I'd have thought it shouldn't act like this. I've tried setting it in the auto rather than on position, but that makes no difference.