The mostly likely cause for your Firewire (IEEE1394b) being unstable relates to having upgraded from Windows XP Service Pack 1 to Windows Service Pack 2. Please refer to following URL for more detailed information: http://support.microsoft.com/kb/885222 The Firewire (IEEE 1394b) driver available from Windows operating system is the most up-to-date version and has been gone through extensive testing and verification before being posted. If you feel the 1394b performance is too slow, we recommend that you download the upgrade patch file from Microsoft's official website. (see link below) http://www.microsoft.com/downloads/details.aspx?familyid=5c076e4c-aec8-434d-9849-e668a50e6e81&displaylang=en