The Node token-bucket pacer used HEAD-drop (emit frames in arrival order,
drop newer ones when over budget). Under the encoder's ~330fps burst (ffmpeg
-re does not reliably throttle YouTube-DASH webm), the viewer was watching
frames ~10s behind live → frozen / 'patah-patah' video while audio (not
rate-limited) played current = desync.
Replace it with a steady setInterval emission clock at videoFps: each tick
emits exactly ONE frame — the NEWEST buffered one — and discards everything
older (tail-drop). At most one frame is ever held, so no backlog and no lag;
the emit clock (not the encoder rate) defines playback speed. Keyframes are
never superseded so the decoder keeps getting IDRs. Audio stays in sync.
asepharyana
8ee32b8df8