ALSA_CONFIG_PATH=/usr/share/alsa/alsa.conf:./dumpasoundrc /home/pi/special/ffmpeg/ffmpeg -f alsa -acodec pcm_s32le -i michooks -f null -
ffmpeg version git-2017-02-05-e57fd92 Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 4.9.2 (Raspbian 4.9.2-10)
  configuration: --extra-cflags=-I/opt/vc/include/IL --enable-nonfree --enable-omx-rpi --logfile=CONFIG.TXT
  libavutil      55. 46.100 / 55. 46.100
  libavcodec     57. 75.100 / 57. 75.100
  libavformat    57. 66.101 / 57. 66.101
  libavdevice    57.  2.100 / 57.  2.100
  libavfilter     6. 73.100 /  6. 73.100
  libswscale      4.  3.101 /  4.  3.101
  libswresample   2.  4.100 /  2.  4.100
ALSA lib dlmisc.c:142:(snd_dlsym_verify) unable to verify version for symbol _snd_pcm_hook_alsadumphook_install
ALSA lib pcm_hooks.c:436:(snd_pcm_hook_add_conf) symbol _snd_pcm_hook_alsadumphook_install is not defined inside [builtin]
[alsa @ 0x21f0430] cannot open audio device michooks (No such device or address)
michooks: Input/output error