no mic on sony vaio vpcw12j1e

[suoko]

i'm experiencing internal mic input problems on this netbook.
i have 2 input in pulseaudio (internal mic and external i guess) but none of them seems working.
i tried modifying /etc/modprobe.d/alsa-base.conf as follow:

options snd-hda-intel power_save=10 power_save_controller=N
->
options snd-hda-intel model=auto power_save=10 power_save_controller=N

and now i see one input source only and internal mic still doesn't work.

$ modinfo snd-intel8x0
filename: /lib/modules/2.6.31-20-generic/kernel/sound/pci/snd-intel8x0.ko
license: GPL
description: Intel 82801AA,82901AB,i810,i820,i830,i840,i845,MX440; SiS 7012; Ali 5455
author: Jaroslav Kysela <perex@perex.cz>
srcversion: 09B55E87B5564D9B98E15DB
alias: pci:v000010B9d00005455sv*sd*bc*sc*i*
alias: pci:v00001022d00007445sv*sd*bc*sc*i*
alias: pci:v00001022d0000746Dsv*sd*bc*sc*i*
alias: pci:v000010DEd0000026Bsv*sd*bc*sc*i*
alias: pci:v000010DEd000000EAsv*sd*bc*sc*i*
alias: pci:v000010DEd000000DAsv*sd*bc*sc*i*
alias: pci:v000010DEd0000008Asv*sd*bc*sc*i*
alias: pci:v000010DEd00000059sv*sd*bc*sc*i*
alias: pci:v000010DEd0000006Asv*sd*bc*sc*i*
alias: pci:v000010DEd0000003Asv*sd*bc*sc*i*
alias: pci:v000010DEd000001B1sv*sd*bc*sc*i*
alias: pci:v00001039d00007012sv*sd*bc*sc*i*
alias: pci:v00008086d00007195sv*sd*bc*sc*i*
alias: pci:v00008086d00002698sv*sd*bc*sc*i*
alias: pci:v00008086d000027DEsv*sd*bc*sc*i*
alias: pci:v00008086d0000266Esv*sd*bc*sc*i*
alias: pci:v00008086d000025A6sv*sd*bc*sc*i*
alias: pci:v00008086d000024D5sv*sd*bc*sc*i*
alias: pci:v00008086d000024C5sv*sd*bc*sc*i*
alias: pci:v00008086d00002485sv*sd*bc*sc*i*
alias: pci:v00008086d00002445sv*sd*bc*sc*i*
alias: pci:v00008086d00002425sv*sd*bc*sc*i*
alias: pci:v00008086d00002415sv*sd*bc*sc*i*
depends: snd-ac97-codec,snd-pcm,snd,snd-page-alloc
vermagic: 2.6.31-20-generic SMP mod_unload modversions 586
parm: index:Index value for Intel i8x0 soundcard. (int)
parm: id:ID string for Intel i8x0 soundcard. (charp)
parm: ac97_clock:AC'97 codec clock (0 = whitelist + auto-detect, 1 = force autodetect). (int)
parm: ac97_quirk:AC'97 workaround for strange hardware. (charp)
parm: buggy_semaphore:Enable workaround for hardwares with problematic codec semaphores. (bool)
parm: buggy_irq:Enable workaround for buggy interrupts on some motherboards. (bool)
parm: xbox:Set to 1 for Xbox, if you have problems with the AC'97 codec detection. (bool)
parm: spdif_aclink:S/PDIF over AC-link. (int)
parm: enable:bool
parm: joystick:int

[suoko]

bump

[suoko]

auto solved by installing
linux-backports-modules-alsa-karmic-generic
linux-backports-modules-karmic

guess they should be installed by default