ffmpeg -f pulse -i default -application lowdelay http://192.168.1.138:8090/feed1.ffm
ffmpeg version 2.6.2 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (GCC) 20150304 (prerelease)
  configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-avisynth --enable-avresample --enable-fontconfig --enable-gnutls --enable-gpl --enable-libass --enable-libbluray --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libschroedinger --enable-libspeex --enable-libssh --enable-libtheora --enable-libv4l2 --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-runtime-cpudetect --enable-shared --enable-swresample --enable-vdpau --enable-version3 --enable-x11grab
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Guessed Channel Layout for  Input Stream #0.0 : stereo
Input #0, pulse, from 'default':
  Duration: N/A, start: 1430083709.570577, bitrate: 1536 kb/s
    Stream #0:0: Audio: pcm_s16le, 48000 Hz, 2 channels, s16, 1536 kb/s
Output #0, ffm, to 'http://192.168.1.138:8090/feed1.ffm':
  Metadata:
    creation_time   : now
    encoder         : Lavf56.25.101
    Stream #0:0: Audio: opus (libopus), 48000 Hz, stereo, s16, 128 kb/s
    Metadata:
      encoder         : Lavc56.26.100 libopus
Stream mapping:
  Stream #0:0 -> #0:0 (pcm_s16le (native) -> opus (libopus))
Press [q] to stop, [?] for help
size=     644kB time=00:00:52.52 bitrate= 100.4kbits/s
video:0kB audio:594kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 8.401291%
Received signal 2: terminating.