Command:
/usr/bin/ffmpeg -i "/path/to/my/file.flv" -vn "/path/to/outputfile.wav"

This works, the audio is extracted. But the first few SILENT seconds are stripped. I'm looking for a way to keep this data.

The outputted data:

/usr/bin/ffmpeg -i "/path/to/my/file.flv" -vn "/path/to/outputfile.wav"
FFmpeg version 0.6.5, Copyright (c) 2000-2010 the FFmpeg developers
  built on Jan 29 2012 23:55:02 with gcc 4.1.2 20080704 (Red Hat 4.1.2-51)
  configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --mandir=/usr/share/man --incdir=/usr/include --disable-avisynth --extra-cflags='-O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -fPIC' --enable-avfilter --enable-avfilter-lavf --enable-libdirac --enable-libfaac --enable-libfaad --enable-libfaadbin --enable-libgsm --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-gpl --enable-nonfree --enable-postproc --enable-pthreads --enable-shared --enable-swscale --enable-vdpau --enable-version3 --enable-x11grab
  libavutil     50.15. 1 / 50.15. 1
  libavcodec    52.72. 2 / 52.72. 2
  libavformat   52.64. 2 / 52.64. 2
  libavdevice   52. 2. 0 / 52. 2. 0
  libavfilter    1.19. 0 /  1.19. 0
  libswscale     0.11. 0 /  0.11. 0
  libpostproc   51. 2. 0 / 51. 2. 0
[flv @ 0xaf78b0]Estimating duration from bitrate, this may be inaccurate
Input #0, flv, from '/path/to/my/file.flv':
  Metadata:
    duration        : 44
    creationdate    : Wed Sep 5 12:20:55
    description     : Wicked Singalong recording
  Duration: 00:00:44.23, start: 0.000000, bitrate: N/A
    Stream #0.0: Video: flv, yuv420p, 352x264, 1k tbr, 1k tbn, 1k tbc
    Stream #0.1: Audio: nellymoser, 22050 Hz, mono, s16
Output #0, wav, to '/path/to/outputfile.wav':
  Metadata:
    encoder         : Lavf52.64.2
    Stream #0.0: Audio: pcm_s16le, 22050 Hz, mono, s16, 352 kb/s
Stream mapping:
  Stream #0.1 -> #0.0
Press [q] to stop encoding
size=    1826kB time=42.40 bitrate= 352.8kbits/s
video:0kB audio:1826kB global headers:0kB muxing overhead 0.002353%