  0: [ 0]   : control
  1:        : sequencer
  4: [ 0- 0]: hardware dependent
 16: [ 0- 0]: digital audio playback
 17: [ 0- 1]: digital audio playback
 22: [ 0- 6]: digital audio playback
 24: [ 0- 0]: digital audio capture
 30: [ 0- 6]: digital audio capture
 33:        : timer
