https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1044150

you need to switch channel mode from 2ch to 6ch and restore this setting by alsactl before pulseaudio start

Simple mixer control 'Channel Mode',0 Capabilities: enum Items: '2ch' '4ch' '6ch' Item0: '2ch

but how can i do this??

amixer -c0 set "Channel Mode" "6ch"

alsactl store

restart pulseaudio server

http://git.kernel.org/?p=linux/kernel/git/tiwai/sound.git;a=blob_plain;f=Doc...

Realtek codecs --------------

* Channel Mode This is an enum control to change the surround-channel setup, appears only when the surround channels are available. It gives the number of channels to be used, "2ch", "4ch", "6ch", and "8ch". According to the configuration, this also controls the jack-retasking of multi-I/O jacks.

can you post the pulseaudio log ?

I don't understand how can pulseaudio server switch to active profile surround51 when blue and pink jacks had not been retasked as output ( Pin-ctls are still IN ) and channel mode is still 2ch.

analog-input rear mic and line-in ports should not be available too.

http://www.intel.com/support/motherboards/desktop/sb/cs-020642.htm#6ch

Jack retasking is a feature that allows an audio jack to support more than one function. For example, the pink audio jack can support microphone input when the system configuration is set to Stereo Mode, and as Center/LFE or Rear Surround (depending on the audio solution used) when set as 6 channel.

Node 0x18 [Pin Complex] wcaps 0x40058f: Stereo Amp-In Amp-Out Control: name="Center Playback Switch", index=0, device=0 ControlAmp: chs=1, dir=Out, idx=0, ofs=0 Control: name="LFE Playback Switch", index=0, device=0 ControlAmp: chs=2, dir=Out, idx=0, ofs=0 Control: name="Rear Mic Boost Volume", index=0, device=0 ControlAmp: chs=3, dir=In, idx=0, ofs=0 Control: name="Rear Mic 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 0x00003736: IN OUT Detect Trigger Vref caps: HIZ 50 GRD 80 100 Pin Default 0x01a19c50: [Jack] Mic at Ext Rear Conn = 1/8, Color = Pink DefAssociation = 0x5, Sequence = 0x0 Pin-ctls: 0x21: IN VREF_50 Unsolicited: tag=03, enabled=1 Power states: D0 D1 D2 D3 EPSS Power: setting=D0, actual=D0 Connection: 5 0x0c* 0x0d 0x0e 0x0f 0x26

Node 0x1a [Pin Complex] wcaps 0x40058f: Stereo Amp-In Amp-Out Control: name="Surround Playback Switch", index=0, device=0 ControlAmp: chs=3, dir=Out, idx=0, ofs=0 Control: name="Line 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 0x00003736: IN OUT Detect Trigger Vref caps: HIZ 50 GRD 80 100 Pin Default 0x0181345f: [Jack] Line In at Ext Rear Conn = 1/8, Color = Blue DefAssociation = 0x5, Sequence = 0xf Pin-ctls: 0x20: IN VREF_HIZ Unsolicited: tag=05, enabled=1 Power states: D0 D1 D2 D3 EPSS Power: setting=D0, actual=D0 Connection: 5 0x0c* 0x0d 0x0e 0x0f 0x26

index: 1 name: <alsa_card.pci-0000_00_1b.0> driver: <module-alsa-card.c> owner module: 5 properties: alsa.card = "0" alsa.card_name = "HDA Intel PCH" alsa.long_card_name = "HDA Intel PCH at 0xf7d00000 irq 44" alsa.driver_name = "snd_hda_intel" device.bus_path = "pci-0000:00:1b.0" sysfs.path = "/devices/pci0000:00/0000:00:1b.0/sound/card0" device.bus = "pci" device.vendor.id = "8086" device.vendor.name = "Intel Corporation" device.product.name = "6 Series/C200 Series Chipset Family High Definition Audio Controller" device.form_factor = "internal" device.string = "0" device.description = "Built-in Audio" module-udev-detect.discovered = "1" device.icon_name = "audio-card-pci" profiles: output:analog-stereo: Analogue Stereo Output (priority 1000) output:analog-stereo+input:analog-stereo: Analogue Stereo Duplex (priority 1010) output:analog-surround-40: Analogue Surround 4.0 Output (priority 700) output:analog-surround-40+input:analog-stereo: Analogue Surround 4.0 Output + Analogue Stereo Input (priority 710) output:analog-surround-41: Analogue Surround 4.1 Output (priority 800) output:analog-surround-41+input:analog-stereo: Analogue Surround 4.1 Output + Analogue Stereo Input (priority 810) output:analog-surround-50: Analogue Surround 5.0 Output (priority 700) output:analog-surround-50+input:analog-stereo: Analogue Surround 5.0 Output + Analogue Stereo Input (priority 710) output:analog-surround-51: Analogue Surround 5.1 Output (priority 3800) output:analog-surround-51+input:analog-stereo: Analogue Surround 5.1 Output + Analogue Stereo Input (priority 3810) input:analog-stereo: Analogue Stereo Input (priority 10) off: Off (priority 0) active profile: output:analog-surround-51+input:analog-stereo sinks: alsa_output.pci-0000_00_1b.0.analog-surround-51/#0: Built-in Audio Analogue Surround 5.1 sources: alsa_output.pci-0000_00_1b.0.analog-surround-51.monitor/#1: Monitor of Built-in Audio Analogue Surround 5.1 alsa_input.pci-0000_00_1b.0.analog-stereo/#2: Built-in Audio Analogue Stereo ports: analog-output: Analogue Output (priority 9900, available: unknown) properties:

analog-output-headphones: Headphones (priority 9000, available: unknown) properties:

analog-input-microphone-front: Front Microphone (priority 8500, available: no) properties:

analog-input-microphone-rear: Rear Microphone (priority 8200, available: yes) properties:

analog-input-linein: Line In (priority 8100, available: yes) properties: