How do I route system audio to specific channel on audio interface? I have a multichannel audio interface connected to my MacBook Pro by USB. I set the interface as the output device in System Preferences &gt; Audio, and the system audio is routed to outputs 1-2. I want to route the system audio to channels 11-12, how can I do this?
In Audio MIDI Setup there is an option to use the device for Sound Output, but there is no way to specify which channels on the device to use.
I am using a 2013 13-inch MacBook Pro running macOS Catalina 10.15.7. The interface is a Soundcraft Signature 12 MTK.
After selecting the device for sound output in System Preferences, you must configure the speaker settings for the device in Audio MIDI Setup:

Open Audio MIDI Setup
Right click on the audio device and select Configure Speakers...
Choose the configuration (e.g. stereo)
Choose the channel destination for each speaker (e.g. left, right)