Comment 33 for bug 27833

The problem seems due to that the usbfs is not mounted on /proc/bus/usb/ but only on /dev/bus/usb. So the udev scripts that use the /proc/bus/usb to upload the firmwares to the attached devices fail to do so since it do not found the respective nodes.

I have found a workaround that I've posted on the duplicate of this bug report here https://bugs.launchpad.net/ubuntu/+source/midisport-firmware/+bug/88923/comments/19