[alsa-devel] Bug: Mic problem, mostly noise, almost no signal, AD1988B on an Asus P5B

Thomas Stenhaug thomas.stenhaug at gmail.com
Mon Feb 16 00:10:03 CET 2009

Current settings and info here:

When I record with these settings, I get a /lot/ of static, and discernible
signal when I tap the microphone on my desktop, or scream into it.
The static gets better when I reduce the capture level, but the signal is
still barely discernible.

The microphone works in the same jack when the computer is running Windows.
 I've also tried a different mic, with the same results.

Playback works flawlessly.

I have seen some posts with people having problems that sound similar, and
some of them seems to be resolved by enabling Mic bias.  However, I don't
have a control called that when I look at alsamixer.
My system is running Debian Etch.  When I started working on this problem, I
used the packages from the "testing" (Etch) repository.  I then pulled in
alsa-base and alsa-utils from the "experimental" repository, and compiled
the 1.0.18a drivers.  This changed nothing in the recordings, nor did any
new controls appear in alsamixer.

I added "snd-hda-intel: model=6stack-dig" to /etc/modprobe.db/alsa-base, and
there was no change in the visible controls.



More information about the Alsa-devel mailing list