When using Sound Manager, ProTools software with PowerMix will only allow audio input via the Macintosh's Built-in hardware. Therefore, you cannot use a MOTU Audio interface as the input device to ProTools software. If the PCI-324 Driver is selected as the input device in the Sound Control Panel, ProTools will return a -50 error and not launch. You can, however, select Built-in as the input device and PCI 324 Sound Manager Driver as the output device in the Sound Control Panel. After doing so, you can run ProTools and monitor your output through the 2408.

Note: If you have OS 8.0 or higher installed, you will need to install the Sound Control Panel which is located in your Apple Extras Folder. You will not be able to see the Sound Manager Drivers with the Monitors & Sound Control panel.