robert@robert-Aspire-5349:~$     ffmpeg -f x11grab -r 25 -s 1024x768 -i :0.0+100,200 -f alsa -ac 2 -i pulse output.flv
ffmpeg version git-2012-06-03-eb7efc1 Copyright (c) 2000-2012 the FFmpeg developers
  built on Jun  3 2012 16:10:35 with gcc 4.6.3
  configuration: --enable-gpl --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libx264 --enable-nonfree --enable-postproc --enable-version3 --enable-x11grab
  libavutil      51. 56.100 / 51. 56.100
  libavcodec     54. 23.100 / 54. 23.100
  libavformat    54.  6.101 / 54.  6.101
  libavdevice    54.  0.100 / 54.  0.100
  libavfilter     2. 77.100 /  2. 77.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0. 15.100 /  0. 15.100
  libpostproc    52.  0.100 / 52.  0.100
[x11grab @ 0x1f27360] device: :0.0+100,200 -> display: :0.0 x: 100 y: 200 width: 1024 height: 768
[x11grab @ 0x1f27360] shared memory extension found
X Error of failed request:  BadMatch (invalid parameter attributes)
  Major opcode of failed request:  140 (MIT-SHM)
  Minor opcode of failed request:  4 (X_ShmGetImage)
  Serial number of failed request:  11
  Current serial number in output stream:  11
robert@robert-Aspire-5349:~$
robert@robert-Aspire-5349:~$
robert@robert-Aspire-5349:~$