My software is Logic Pro 9 and my Hardware is an Apogee Duet. My research has told me I need to make my bus [(Bus 20) with all of the tracks sent to it] to Output 3+4. The problem is, Logic Pro only allows me to send to Output 1+2 and I only have two outputs which go to my two speakers. How do I create a headphone mix with only Output 1+2?

Hi Robert, Welcome to the forums! The Apogee Duet is a 2 input and 2 output audio interface... this means you only have the option to use the Output 1-2, which is why there is no Output 3-4 available from within Logic. There are two real solutions... either get an interface with more outputs, or try creating an aggregate device. An Aggregate device combines the inputs and outputs of two audio interfaces. This will give you a greater number of inputs and outputs to play with. As your Mac has a built-in audio interface, if you create an aggregate device combining the Duet and the Built-in you will in theory have 4 outputs and could use the headphone port on your Mac as the Headphone Mix output. Check this document out for how to create an aggregate device: [url]http://support.apple.com/kb/HT1215[/url] Cheers Rounik