[wplug] debugging audio, please help

[Mike Sussman]

Folks,  I have a crazy problem that I need help debugging.

I have a HP dv9600 on which I have installed Kubuntu Hardy (8.04). Skype
was working but it stopped working and I am looking for ideas about
debugging the problem.  I strongly suspect the problem is some setting.

I know the hardware and basic software setup work because
(a) The live-CD, with Skype installed using dpkg, works.
(b) My system used to work.
By "work" I mean having both output from and input to Skype working.
These are tested by making a Skype test call.

I checked the audio settings using alsamixer on both the live-CD and my
installed system, and they are the same.  But it stopped working soon
after I tried playing a (bad) audio file.  After playing that audio
file, I had to bring alsamixer up and restore its volume settings to
reasonable (nonzero) values in order to hear any sound from any source.
Currently all audio I have tried, including Skype, plays, but I am
unable to get Skype to hear my voice.  (No hiss or anything--as if the
built-in microphone were turned off.)

SO, there must be more settings somewhere than alsamixer knows about.
Any help would be appreciated.
-- 
                       Mike Sussman
                       sussmanm at math.pitt.edu