Hello,
I have an issue I'd like to help completely solve. Unfortunately I only have a tenuous grasp of what is actually going on so some of this could be wrong/include errors.
Here's what I know.
1) I have the following hardware (alsa-info attached). 2) The internal microphone requires that the mic boost channel be something other than 0 to function properly. 3) Changing what pulseaudio expects things to be labelled causes the problem to go away. (via the attached patch to /usr/share/pulseaudio/paths/analog-input-mic.conf).
From the discussion with David Henningsson (diwic on IRC). It seems that pulse doesn't expect a Mic Boost channel to be used with internal microphones. As such to fix this particular hardware, the driver would need to make the internal mic boost be labelled "Internal Mic Boost" as opposed to Mic Boost, which is then is used for both external and internal mics.
I'd love to be able to help any way I can to get these fixed once and for all. Let me know if you need more information or what not.