usb hdd not scanned when connected via usb hub

I have Volumio 1.1 beta installed on ver. B Raspberry Pi. When I connect my hdd through usb hub the system sees the storage but Volumio does not pick it up for scannning. The device is seen as sda on usb dev id 6. It all works well however when I connect the same disk to the on-board ports of the Raspberry Pi - the library is created and can be browsed. It’s strange that the same device /dev/sda is not picked up on a different usb dev id, I’d assume that mount should be relative depending on the device rather than it’s physical location.
I did not have much time for investigation yesterday but will try to dig deeper in the evening. Maybe someone has any ideas?

Yes, you should add /dev/sda6 in /etc/usb.conf , I wasnt’ thinking someone could reach /sda6…

Let me know!