On the back of the Big Knob, next to the USB connector, is a toggle switch labeled USB REC SRC SELECT. By default, this switch is disengaged, allowing 2-track monitoring sources to be sent to the computer for USB recording. This includes any source with its 2-track button engaged, which can cause feedback as the computer records audio being sent back to the Big Knob.
If you're overdubbing tracks with pre-recorded material, engage the switch to send inputs 1 and 2 to the computer, functioning more like a typical audio interface. You can also disable monitoring in your DAW to prevent feedback, but this will still re-record existing tracks.
For merging multiple sources before reaching your DAW or broadcasting without live USB playback monitoring, keep the USB Source Selection disengaged on 2-track. This allows sending all 6 inputs plus USB to the computer simultaneously.
To summarize:
Disengaged switch: record all monitored sources.
Engaged switch: record only inputs 1 and 2, regardless of monitoring.
Experiment with both switch positions to find the best option for your needs!
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