Faderport fader not moving but otherwise good...

OK. I've just finished setting up my new studio machine, a 2015 Mac Pro. I decided not to migrate anything from my old iMac and do a fresh install of everything because I'm a ****** for punishment.

The Faderport was working perfectly fine on the old iMac in Studio One Pro. But seems reluctant to play ball on the new one!!!!

It is up and ruing for the most part, but the fader isn't matching the chaels currently selected. No movement at all on the fader.

If I move the fader it inputs correctly to the software and the fader moves on screen. But the fader is not motorised whatsoever.

Done all the usual stuff and power cycled, unplugged and rebooted to no avail. Did a firmware update and no difference.

Can anyone offer advice on what else to try?

Oh yeah, the machine is ruing Sierra and the latest version of Studio One Pro.

Cheers, Ross