Dolby TrueHD: 100 buffers queued in out_0_0, something may be wrong

[flx90]

I'm trying to convert Dolby TrueHD embedded in mkv container to alac and mux it into mp4(m4v)-container.
I get the following message: [out_0_0 @ 000000000045a0c0] 100 buffers queued in out_0_0, something may be wrong.

This can be replicated using one of those Dolby Trailers: ​https://thedigitaltheater.com/dolby-trailers/

The message occurs with every output (alac, flac, wav, ...).

Uncut console output:

ffmpeg -i Dolby_Bit_Harvest_Lossless-thedigitaltheater.mkv -map 0:1 -c:a alac Dolby_Bit_Harvest_Lossless-thedigitaltheater.m4v
ffmpeg version N-93022-g260f1960e7 Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 8.2.1 (GCC) 20181201
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
  libavutil      56. 26.100 / 56. 26.100
  libavcodec     58. 44.100 / 58. 44.100
  libavformat    58. 26.100 / 58. 26.100
  libavdevice    58.  6.101 / 58.  6.101
  libavfilter     7. 48.100 /  7. 48.100
  libswscale      5.  4.100 /  5.  4.100
  libswresample   3.  4.100 /  3.  4.100
  libpostproc    55.  4.100 / 55.  4.100
Input #0, matroska,webm, from 'Dolby_Bit_Harvest_Lossless-thedigitaltheater.mkv':
  Metadata:
    encoder         : libmakemkv v1.9.5 (1.3.0/1.4.1) win(x64-release)
    creation_time   : 2015-08-29T18:56:26.000000Z
  Duration: 00:00:11.01, start: 0.000000, bitrate: 12615 kb/s
    Stream #0:0(eng): Video: h264 (High), yuv420p(progressive), 1920x1080, SAR 1:1 DAR 16:9, 23.98 fps, 23.98 tbr, 1k tbn, 47.95 tbc
    Stream #0:1(eng): Audio: truehd, 48000 Hz, 7.1, s32 (24 bit) (default)
    Metadata:
      title           : Surround 7.1
Stream mapping:
  Stream #0:1 -> #0:0 (truehd (native) -> alac (native)) Press [q] to stop, [?] for help Output #0, ipod, to 'Dolby_Bit_Harvest_Lossless-thedigitaltheater.m4v':
  Metadata:
    encoder         : Lavf58.26.100
    Stream #0:0(eng): Audio: alac (alac / 0x63616C61), 48000 Hz, 6.1(back), s32p (24 bit), 128 kb/s (default)
    Metadata:
      title           : Surround 7.1
      encoder         : Lavc58.44.100 alac
[out_0_0 @ 000000000045a0c0] 100 buffers queued in out_0_0, something may be wrong.
[truehd @ 0000000002ff7640] End of stream indicated.
size=    5179kB time=00:00:11.09 bitrate=3824.1kbits/s speed=22.9x    
video:0kB audio:5177kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.040051%

[Hendrik]

Is something actually wrong, or does the file come out fine?

[flx90]

File is fine.

[Carl Eugen Hoyos]

Thank you Hendrik, I wasn't sure if I remember the issue correctly.

[Balling]

Some other file I found is indeed bitperfect with official decoder, that dies not have such a warning (it is ffmpeg based).