I am looking for the cause of this happening. My work-around is I eject all and then unplug and plug back in. I'd prefer if I didn't have to do this all the time. On a related note it seems that every time I close the cover of my Macbook Pro and then reopen it later I get 3 popups - 1 for each partition - saying that my external hard drives were shut down incorrectly but when I go to my desktop they are there.