Yes I wait for the arrows to stop spinning
. I wait until I can access my books, then re-plug in the device. Wait until it's recognized, open calibre. Wait and I still get an error. I've deleted the media.xml file at least a dozen times appropriately.
Also I do wait for the hourglass to stop moving, then I attempt to upload a book to the device. The hourglass does it's thing, it stops and I get the error listed above.