Is your BMC not working as well?
I've had the same issue with one of my Blackbirds and contacted RaptorCS;
I know there was a manufacturing process change to fix data corruption seen on the first handful of boards, it's very possible this one shipped out prior to the change.
They fixed it by providing an update bundle which I then flashed. When you contact them, provide your ports MAC addresses so can embed that in the image.
They provided the following commands to flash the new image:
set +e
echo 0004:01:00.1 > /sys/bus/pci/drivers/tg3/unbind
set -e
bcmflash -t raw -i 1 -r bcm5719.rom[
After powering down and removing the system from your wall socket, boot it up again and it should work as expected.