Pin recording audio sample rate at 48 kHz - #11092
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loudnorm analyses at 192 kHz and declares that as its output rate, so ffmpeg negotiated the AAC encoder's 96 kHz ceiling during finalize, resampling captured 48 kHz audio up to 96 kHz (Fixes omacom/omarchy# 10970).
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Every screen recording made with audio was written at 96 kHz AAC instead of the 48 kHz the recorder captured, because ffmpeg's
loudnormfilter analyses at 192 kHz and declares that as its output rate. With no-arpinned, the finalize pass negotiated that against the AAC encoder's 96 kHz ceiling, silently resampling the audio up. 96 kHz AAC is poorly supported downstream — DaVinci Resolve, for one, imports the clip with correct metadata but decodes no samples (silent audio, blank waveform) — and it costs bitrate for no benefit since the source is 48 kHz.Fix by adding
-ar 48000to the finalize invocation infinalize_recording(). Loudness normalization is unaffected: a -21.1 dB source still lands at -13.6 dB against the -14 LUFS target.Fixes #10970