Comment 2 for bug 682617

1) Is this internal mic / external front mic / external back mic, or all of them? What mics are present?

Notice that the following volume controls are off, and input source is set to back mic:

Simple mixer control 'Front Mic Boost',0
  Capabilities: volume penum
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 3
  Front Left: 0 [0%] <-------------
  Front Right: 0 [0%] <-------------
Simple mixer control 'Mic Boost',0
  Capabilities: volume penum
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 3
  Front Left: 0 [0%] <-------------
  Front Right: 0 [0%] <-------------
Simple mixer control 'Capture',0
  Capabilities: cvolume cswitch penum
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 31
  Front Left: Capture 11 [35%] [0.00dB] [off] <-------------
  Front Right: Capture 11 [35%] [0.00dB] [off] <-------------
Simple mixer control 'Capture',1
  Capabilities: cvolume cswitch penum
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 31
  Front Left: Capture 0 [0%] [-16.50dB] [on] <-------------
  Front Right: Capture 0 [0%] [-16.50dB] [on] <-------------
Simple mixer control 'Input Source',0
  Capabilities: cenum
  Items: 'Mic' 'Front Mic'
  Item0: 'Mic' <-------------
Simple mixer control 'Input Source',1
  Capabilities: cenum
  Items: 'Mic' 'Front Mic'
  Item0: 'Mic' <-------------