This item has been flawless and in use for the last year at my studio.  Works 100%.  We will not accept a return based on compatibility issues with your system.  The unit is functioning perfectly and that is what we are selling here.  Please check all system requirements before ordering!From the RME Website: The HDSPe MADI is RME's both inexpensive and outstanding PCI Express card with MADI interface. HDSPe MADI is based on the award-winning HDSP MADI card, and represents the new top model of this world-wide successful card line. The PCI Express card consequently uses all advantages of the MADI format, the professionals' multi-Channel audio interface, offering 64 channels of 24-bit audio at a sample rate of up to 48 kHz, 32 channels at up to 96 kHz and 16 channels at up to 192 kHz. Transmission is done via a single line, either coaxial with BNC plugs or by fiber cable. In both cases more than 100 m cable length can be achieved. Compared with the (Standard PCI version), the express card offers some new features: Support of higher sample rates than 96 kHz, more features in TotalMix (phase and internal loopback per channel, +6 dB gain for the hardware outputs), and the direct support of the . HDSPe MADI provides even lower latencies, making the card the perfect partner for live recording and live mixing applications. The analog monitor output is equipped with the low-latency converter technology of the , thus guaranteeing stunning SNR and THD values too. HDSPe MADI is fully compatible to all devices with MADI interface. In combination with the an 8 x ADAT optical PC interface is realized, unbeatable in price and performance. With the a bidirectional AES/EBU frontend with 64 channels is available. On a powerful PC/Mac three HDSPe MADI can be used in a combination, providing 192 inputs and 192 outputs on a single workstation simultaneously.