Open the PCI-424 CueMix Console and unmute the Master Fader. Above the master fader you will find a drop down menu, allowing you to select from all the stereo outputs from the MOTU interface(s) connected to the PCI-424. Each output is a bus. With the PCI-424, you can assign multiple inputs through these busses. Select an output bus and unmute the inputs you wish to hear through the selected bus output. The DSP and PCI meters in the top right-hand corner will help you monitor the performance of your PCI-424 card. Once you've set up CueMix, you will then be able to directly monitor from the unmuted inputs while recording into Sonar.