Joel@localhost:~> amixer contents
numid=3,iface=MIXER,name='PCM Playback Switch'
  ; type=BOOLEAN,access=rw---,values=2
  : values=on,on
numid=4,iface=MIXER,name='PCM Playback Volume'
  ; type=INTEGER,access=rw---,values=2,min=0,max=43,step=0
  : values=1,1
numid=1,iface=MIXER,name='Capture Switch'
  ; type=BOOLEAN,access=rw---,values=2
  : values=on,on
numid=2,iface=MIXER,name='Capture Volume'
  ; type=INTEGER,access=rw---,values=2,min=0,max=23,step=0
  : values=23,23
Joel@localhost:~>