FireWire requires optional X-FireWire card, 2-in (XLR balanced analog), 2-out (XLR balanced analog), AES digital i/o, optical i/o, S/PDIF i/o, word clock i/o, CODA Audio Finishing Module (Aptomizer nomalization, Sample Rate Conversion, and UV22HR dithering), SoftLimit, full metering, MIDI i/o.