hercules 4 mx not recognised

hey,

i recently picked up one of these units for the first time, and i cant seem to get it connected to my desktop machine, though it works fine with my laptop.

machine:
os: windows 8.1 x64
16gb ram
intel i5 haswell
onboard sound  
750w psu
lots of usb ports

the unit:
hercules 4 mx

i followed the instructions last night but in the end gave up and got it working with my laptop (windows 7 lenovo). i was having problems with the controller firmware not updating through my desktop, but it seemed to work fine with the same cable with my laptop.

now i am getting "usb device not recognised" errors when i connect, and it doesnt think the device is connected anymore.

in device manager, with hidden devices showing, i see this:

any pointers?