Why is the FireWire 800 transfer rate on Mac OS X so slow?
We found that under some circumstances, the FireWire 800 transfer rate on Mac OS X is much slower than expected. Instead of the usual read speed of about 60-80 MB/s, it only reaches about 40 MB/s.
If you encounter this problem and have firmware password protection on your Mac enabled, please disable it and then test it again. For more information about firmware password protection, please refer to this article at http://support.apple.com/kb/HT1352.
If this does not solve your problem, please contact support.