Similarily, you cannot aggregate Onyx-i mixers with Onyx Blackbirds.
This means you cannot connect multiple Onyx-i devices to the same computer for simultanous use. *PC Driver v1.9 and Mac OS Core Audio for Onyx-i mixers do not support device aggregation.
If you need to quickly see which driver you need to install on your system for your mixer or interface, you can cross reference it with your operating system using this chart.