Music can sit comfortably under one sentence and cover the next quiet word. Automatic ducking uses a control track to trigger a temporary reduction in another track, but the result still needs a listening pass.
The Audacity Auto Duck manual describes using an unselected control track below the selected tracks. In a speech-and-music arrangement, the voice provides the trigger while the selected music receives the reduction.
Test a passage with a pause
Work on a short copy containing a complete sentence, a breath, and the next sentence. A test containing uninterrupted speech will not reveal how the music returns in the gaps.
Listen for three things: whether the first word remains clear, whether the music surges during a brief pause, and whether its return after the final sentence feels deliberate. Adjust one parameter before comparing again. Changing the threshold, reduction, and timing together makes it difficult to understand which change helped.
Keep the unducked music available so you can compare at a sensible listening level. The objective is intelligible speech with an intentional musical shape, rather than the largest possible reduction. If one isolated phrase behaves differently, a manual edit may be easier to understand than forcing the whole passage through another global adjustment.
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