Fireface800 Problem

Can anybody tell me if a firewire 9P to 400 6P lead works with a fireface800 soundcard within a new current MacBook old MacBook Pro with original lead insert was fine and found my fireface800 immediately...I am having trouble getting my new mac/logic9 to find the fireface800 sound card and I am not sure if it is this particular lead causing the problem or any other steps I need to perform? HELP!!!:brkwl: