i made A LOT of debugging, and i found this issue is only related with usb 3.0 ports.
ubuntu 10.10, 13.04, 13.10 + usb 2.0 -> ok (tested on 3 computers)
ubuntu 10.10, 13.04, 13.10 + usb 3.0 -> no (tested on 2 computers)
windows vista + usb 2.0 -> ok (tested on 1 computer)
windows vista + usb 3.0 -> no (tested on 1 computer)
it may look like the scanner could not be compatible with usb 3.0, but vuescan
perfectly works on ubuntu (13.04 and 13.10) and usb 3.0
i spent some time searching for a solution to this bug, but i could not find any...