I see you have got FW card, so IRQ shouldnt cause the problems. anyway, http://en.wikipedia.org/wiki/IRQ_conflict
It seems, there must be something wrong with the card. Did you update the firmware??? If not, then go to Focusrite site and download/install it. http://www.focusrite.com/support/sof...ire_pro_10_io/
There can be also problems with FW controller,. Update the drivers for your motherboard, then try to install SP3 (it is sorting some strange behavior and problems with FW controller). then if nothing helps, i would suggest you to send the card back to shop..