SD1000 is powered by external power supply, not USB.
This, is 100% correct, Ketron does not support the SD1000 working over usb powered connector, they just can not guarantee it working, be ause it uses more power then the USB interface maximum supports...
Just look up the power consumtion of the SD1000 and then have a look at the USB port specs... If it works for you, then you are lucky..