If a deck is loaded (dj keeps playing across pieces, its audio is already in the clip via the output-mix tap), each tape stamps the song title/ artist into the moov metadata at start and appends a top-level 'skip' box after the trailer with JSON: song identity, songStart (position when recording began), songEnd (position at the cut), duration, speed. Players ignore the box; editors/tools read it to resync clips onto the track's timeline for music videos. cap shows the live track+position in its idle chrome. (The @minanimals music-video flow: scrub anywhere, hold space, end up with pre-synced takes.)