Audio Mark Start

Sets the point on the output timeline where the audio overlay begins, in seconds.

audio-mark-start defaults to 0.0 (the overlay starts at the very beginning of the output). The value is measured on the output timeline — after any video-clip-* trims and video-speed adjustments — not the original source.

Use audio-mark-start to delay the overlay so it enters partway through the video. Before the start time the overlay is silent; after it the overlay plays normally until audio-mark-end or the end of the output.

Each layer takes its own [N] suffix: audio-mark-start[1]=15.