fix: resolve passthrough audio not flowing in media player bridge#486
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fix: resolve passthrough audio not flowing in media player bridge#486
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Three issues prevented audio from reaching downstream blocks (e.g. mpegtssrt) in passthrough mode: 1. clocksync in PAUSED state silently drops buffers — its internal flushing flag is only cleared during PAUSED→PLAYING transition. When pad-added fires during pipeline preroll, sync_state_with_parent leaves clocksync in PAUSED because the pipeline hasn't reached PLAYING yet. Fix: set clocksync to PLAYING explicitly. 2. Upstream pad linked before elements are started — urisourcebin's internal multiqueue pushes buffered data the instant a pad is linked. If clocksync is still in NULL/READY state, the push returns FLUSHING and the multiqueue permanently kills that stream's thread. Fix: link downstream first, start elements, then link upstream last. 3. push_sample error kills appsink permanently — the main pipeline's appsrc may not be ready when the first samples arrive (internal pipeline starts before main pipeline). The ? operator on push_sample returns FlowError::Error which GStreamer treats as a permanent failure. Fix: return Ok on transient errors to keep the bridge alive. Video worked by luck: it prerolled first (before adding a sink dropped the pipeline to PAUSED) so its clocksync got PLAYING state, and its multiqueue thread hadn't started pushing when the link was made. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
Changes
sync_state_with_parent()which leaves it in PAUSED during prerollWhy video worked but audio didn't
Video prerolled first (before adding a sink dropped the internal pipeline's aggregate state to PAUSED), so its clocksync got PLAYING state. Audio pad-added fired second, by which time the pipeline was in PAUSED, leaving audio clocksync stuck.
Test plan
identity -> aacparse (AAC) -> mpegtsmux🤖 Generated with Claude Code