[jpsts]

Summary

A live MPEG-TS source whose audio runs more than a minute from its video could not play on the software path with a rewind buffer: FFmpeg's 33-bit wrap correction puts the audio about 26.5 h ahead, the audio sets the live edge, and the rewind buffer discards every video keyframe as older than its window.

What changed

• LiveAudioAxis: audio more than 30 s from the video moves onto the video's axis, aligned on arrival, in both live loops (rewind and no rewind).
• Audio that disagrees for a moment (a seam one stream crosses first) is held back only while video is moving; a sparse picture over continuous sound is left alone.

Test plan

• LiveAudioAxisTests.
• aetherctl play --live --sw --dvr-window 600 on a local real-time stream with audio 274 s behind video, a Mac, macOS 27: stock 7.56.0 logs 15 eviction recoveries and 15 underruns in 30 s with the clock stopped; with this change none, 50 fps, clock running.
• Full suite on a Mac: one failure, LAN peers cannot take the slots kept for loopback, which times out the same way on stock 7.56.0.
• Not measured: A/V sync on a real source. Aligning on arrival is only as exact as the source's interleave.