Yes I did. I read that you can have them both connected so I connected the USB cable based on this FAQ assuming the USB would let me update the firmware (which appeared to be successfull for both) and after disconnecting the USB, the firewire driver. I also noticed that in Protools using the USB I can only get 2 channels, but as I said its early days so it's maybe just the bandwidth on my USB.

FAQ Can I use the UCX on a USB and FireWire port at the same time?

No. You can connect both and install both drivers, but the UCX will use only one (USB has priority).

So how do I get it to use FW. I disabled the USB driver, rebooted, and now I am not even getting the red host light, just PH on the display. I reinstalled the FW but nothing's happening.

Ok I've tried everything I can think of, new firewire cable, checked the firewire on the PC by connecting a Profire 610. Tried booting firewire only, and then with the power supply and only getting red host light and PH, nothing reported in device manager. Firewire cable fits snug in the socket and it's supplying power. Tried again with a clean install of Win 7, the same. Reflashed the unit even though it reported ok and still no joy. Unless there is something else anyone can suggest it's going back. Not the kind of hassle you expect from a soundcard costing a grand.

Another thing when using it under USB, and when I say using it I've not had a chance to record anything, the mixer seemed to have loaded at the wrong resolution so only the top two thirds and left two thirds of the mixer was in view, and clicking on the screen was for example toggling a mute switch in a different part of the display. So a separate issue hopefully.