Then you can just mute the other audio tracks, and left one of ‘commentary track’, export it as it’s own.
But, however, not sure of the other authoring tools that able to combine 2 different audio and let viewer choose the preferred audio track to listen.
In DVD Authoring, I guess you can put audio track 1 and 2. – the most far I can think will MKV compilation – but never tried… so I don’t know about it.
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