I'm searching for a simple and straightforward way to double the normal output, i.e. normally I use channel 1 & 2 for driving a pair of loudspeakers. Now I want to output an identical copy to channels 3 & 4 (not driving loudspeakers, but feeding into another system) without re-programming all my existing sounds. I thought, something like this:
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could do the job, but it doesn't. Is something like this:
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the only possibility (which means re-working the existing sounds)? Or is there another fine trick?