OSX 10.6.4 macbook pro fireface 800 plug wt firewire 400 wt original cable.

Hello everybody!
I have some problems with the playback in DP7, and LIVE8 some times (even often) it's freeze and make a really big noise. I got the last driver 2.72, and for the firmware it's a bit more tricky cause i got the 2.77 version which is the one for windows. Once I had to install my fireface in windows and so change the firmware. Since when i whant to install the mac firmware which  is 2.70 version the firmware updater said to me that it's up-to-date with the 2.77 revision (the windows one i guess). Could be the origine of my problem? How can i get back the right firmware? Thanks for help. Sylvain Jacques.