hi,

run across a sample containing aac audio that ffmpeg fails on.
it churns out a stream of errors
first "Unable to find ADTS syncword", then "Unexpected channel configuration error"


ffmpeg -i aac-channel-conf.aac o.wav
FFmpeg version SVN-r13656, Copyright (c) 2000-2008 Fabrice Bellard, et al.
  configuration: --enable-memalign-hack --enable-postproc --enable-swscale --ena
ble-gpl --enable-liba52 --enable-libfaac --enable-libfaad --enable-libgsm --enab
le-libmp3lame --enable-libnut --enable-libvorbis --enable-libtheora --enable-lib
xvid --enable-libx264 --disable-ffserver --disable-ffplay --enable-avisynth --en
able-small --enable-pthreads --extra-ldflags=-static --extra-cflags=-mtune=penti
um4 -mfpmath=sse -msse -fno-strict-aliasing
  libavutil version: 49.7.0
  libavcodec version: 51.57.1
  libavformat version: 52.14.0
  libavdevice version: 52.0.0
  built on Jun  4 2008 23:30:39, gcc: 4.3.0
Input #0, aac, from 'aac-channel-conf.aac':
  Duration: 00:02:20.70, bitrate: 65 kb/s
    Stream #0.0: Audio: libfaad, 22050 Hz, stereo, 65 kb/s
Output #0, wav, to 'o.wav':
    Stream #0.0: Audio: pcm_s16le, 22050 Hz, stereo, 705 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
Press [q] to stop encoding
Multiple frames in a packet from stream 0
[libfaad @ 0094F29C]faac: frame decoding failed: Unable to find ADTS syncword
Error while decoding stream #0.0
Multiple frames in a packet from stream 0
[libfaad @ 0094F29C]faac: frame decoding failed: Unable to find ADTS syncword
Error while decoding stream #0.0
Multiple frames in a packet from stream 0
[libfaad @ 0094F29C]faac: frame decoding failed: Unable to find ADTS syncword
Error while decoding stream #0.0
Multiple frames in a packet from stream 0
[libfaad @ 0094F29C]faac: frame decoding failed: Unable to find ADTS syncword

[snip]

Error while decoding stream #0.0
[libfaad @ 0094F29C]faac: frame decoding failed: Unexpected channel configuratio
n change
Error while decoding stream #0.0
[libfaad @ 0094F29C]faac: frame decoding failed: Unexpected channel configuratio
n change
Error while decoding stream #0.0
[libfaad @ 0094F29C]faac: frame decoding failed: Unexpected channel configuratio
n change
Error while decoding stream #0.0
[libfaad @ 0094F29C]faac: frame decoding failed: Unexpected channel configuratio
n change
Error while decoding stream #0.0
[libfaad @ 0094F29C]faac: frame decoding failed: Unexpected channel configuratio
n change
Error while decoding stream #0.0
[libfaad @ 0094F29C]faac: frame decoding failed: Unexpected channel configuratio
n change
Error while decoding stream #0.0
[libfaad @ 0094F29C]faac: frame decoding failed: Unexpected channel configuratio
n change
Error while decoding stream #0.0
[libfaad @ 0094F29C]faac: frame decoding failed: Unexpected channel configuratio
n change
Error while decoding stream #0.0
size=    1024kB time=11.89 bitrate= 705.6kbits/s
video:0kB audio:1024kB global headers:0kB muxing overhead 0.004196%



mplayer plays back the audio file without error,
and manages to dump to pcm despite errors:

mplayer aac-channel-conf.aac -ao pcm:fast
MPlayer Sherpya-SVN-r26446-4.2.3 (C) 2000-2008 MPlayer Team
CPU: Intel(R) Pentium(R) 4 CPU 2.40GHz (Family: 15, Model: 2, Stepping: 9)
CPUflags:  MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Compiled for x86 CPU with extensions: MMX MMX2 SSE SSE2
116 audio & 237 video codecs

Playing aac-channel-conf.aac.
libavformat file format detected.
[lavf] Audio stream found, -aid 0
==========================================================================
Opening audio decoder: [faad] AAC (MPEG2/4 Advanced Audio Coding)
AUDIO: 44100 Hz, 2 ch, s16le, 65.6 kbit/4.65% (ratio: 8204->176400)
Selected audio codec: [faad] afm: faad (FAAD AAC (MPEG-2/MPEG-4 Audio) decoder)
==========================================================================
[AO PCM] File: audiodump.wav (WAVE)
PCM: Samplerate: 44100Hz Channels: Stereo Format s16le
[AO PCM] Info: Faster dumping is achieved with -vc null -vo null -ao pcm:fast
[AO PCM] Info: To write WAVE files use -ao pcm:waveheader (default).
AO: [pcm] 44100Hz 2ch s16le (2 bytes per sample)
Video: no video
Starting playback...
FAAD: error: Unable to find ADTS syncword, trying to resync!
FAAD: Failed to decode frame: Unable to find ADTS syncword
FAAD: error: Unable to find ADTS syncword, trying to resync!
FAAD: Failed to decode frame: Unable to find ADTS syncword
FAAD: error: Unable to find ADTS syncword, trying to resync!
FAAD: Failed to decode frame: Unable to find ADTS syncword


Exiting... (End of file)