TrueHD/Atmos passthrough with Frame Rate Matching enabled never engaged
the receiver on the mpv backend (Ugoos SK1 -> Denon AVR): the display
mode switch settles 2 s before the audio output opens, but some HDMI
chains are still renegotiating audio then, so the IEC 61937 track binds
a half-negotiated route and the sink never locks onto the MAT
bitstream - for the whole session. The same file with Frame Rate
Matching off, or on ExoPlayer, engages Atmos immediately: media3
rebuilds its sink when the audio device set changes, while mpv's
ao_audiotrack never revisited a track once created.
libmpv v1.2.1 polls AudioTrack.getRoutedDevice from the AO thread and
reloads the AO when the route changes - or vanishes and rebinds - under
a live IEC or raw passthrough track, reopening it against the settled
route. PCM tracks are exempt, and audiotrack-route-reload=no is the
escape hatch.
close#2190
edde746
39ee089212