Is Saffire PRO 40 a USB device?
No, Saffire PRO is a dual port Firewire 400 device. USB can occasionally be quite unstable; Firewire 400 offers better stability. There are two Firewire ports on the Saffire PRO so that you can chain/connect additional Firewire devices (such as hard drives) to your computer, even though your computer may only have one Firewire port. NOTE: Some third party devices may require an independent firewire port. Depending on the number of channels being used, Saffire PRO 40 may also benefit from its own dedicated firewire port.