When playing a video file, we'd want to hear it, but when switching to a live shot, we don't always want to hear the audio back. Storing it for each shot would solve this issue.
With Mics we have a "mix minus" feature so the audio goes live but you don't hear it in the monitor. You'd like that with files as well from what I understand. Certainly make the feature request. Wirecast Feature Request Form
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