Comment 65 for bug 1332900

it is because you retask the node as line out jack

Node 0x1a [Pin Complex] wcaps 0x40058f: Stereo Amp-In Amp-Out
  Control: name="PCM Playback Switch", index=0, device=0
    ControlAmp: chs=3, dir=Out, idx=0, ofs=0
  Control: name="Line Out Jack", index=0, device=0
  Amp-In caps: ofs=0x00, nsteps=0x03, stepsize=0x27, mute=0
  Amp-In vals: [0x00 0x00]
  Amp-Out caps: ofs=0x00, nsteps=0x00, stepsize=0x00, mute=1
  Amp-Out vals: [0x00 0x00]
  Pincap 0x0000373c: IN OUT HP Detect
    Vref caps: HIZ 50 GRD 80 100
  Pin Default 0x411111f0: [N/A] Speaker at Ext Rear
    Conn = 1/8, Color = Black
    DefAssociation = 0xf, Sequence = 0x0
    Misc = NO_PRESENCE
  Pin-ctls: 0x40: OUT VREF_HIZ
  Unsolicited: tag=03, enabled=1
  Power states: D0 D1 D2 D3 EPSS
  Power: setting=D0, actual=D0
  Connection: 3
     0x0c* 0x0d 0x0e