o and im running pro tools version 6.4

coul'd be a driver problem, maybe 6.4 is not compatible with tiger yet, why did you upgraded to tiger already anyway??? did you had any problems before?, if your system works, i wouldn't change anything, specially not upgrading the OS all the time, or at least not if there is not a particular reason for it, it usually causes to much trouble...

i even use some real ancient versions, because they work fine... that's all you need really, isn't it??

i probably would swapp back to 10.3.8 or something, in my case (running logic) an update from 10.3.3 to 10.3.4 caused me a hell lot of trouble... i swapped back to 10.3.3 all fine...

mbox will not work under 10.4!!

and certainly not with 6.4!!!

some time soon there will be a version 6.9.x that wil work

so backup your harddisk and downgrade.... to 10.3.8..... 10.3.9 will cause trouble....

install anything 10.3 and upgrade with this...

http://www.apple.com/support/downloads/macosxupdate1038combo.html

here we go,
all this software crap, only upgrade if you are really forced to!!!, otherwise stick with what is working stable, just my personal advise...

axel