Although there are many different types and brands of firewire cards in existence, only some of them are suitable for real-time audio streaming.
If you are unsure about the compatibility of your firewire chipset, please download this tool, and run OHCItool.exe. From there, click 'scan'. If the end result reads "Compatible, no known issues", then the firewire chipset will work. If it reads "This controller is not compatible with DICE drivers" or "Compatibility Unknown", then you'll need to replace your firewire card with a compatible one from our Firewire Compatibility Article.
Please note that you need to be on the Standard Windows Driver to use the OHCI Tool. If you are on Windows 7 using the Legacy Driver please revert to Standard Driver following this guide.
If you're still having issues, please contact our tech support team by clicking "Contact Us" at the top of the page.