Found while testing crates/engine/src/cmd/track_more.rs:370-392 (write_rtp); playback side: crates/mix/src/lib.rs:1526-1527 Co-Authored-By: Claude Haiku 5.5 <noreply@anthropic.com> Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>