Distorted Audio - unless at 50 or 100% - Nvidia Nforce2 AC97

Hi All,

I’ve gone through the process of installing and setting up OpenSuse, which has been fairly streamlined.

The only problem I am having is with my Soundcard
the audio coming out of it is highly digitally distorted unless
I set it to 100% or 50% in the sound preferences section. Once this is done, the audio quality is still fairly awful, but doesn’t sound like my guitar’s fuzz box!

I’m assuming this is some sort of drivers issue and I have a few options in my yast audio configuration that I’m unsure what to do with.
they are as follows:

AC’97 Codec Clock (0 = auto-detect) ac97_clock 0
AC’97 workaround for strange hardware ac97_quirk 1
Enable workaround for buggy interupts on some motherboards buggy IRQ 0
Enable workaround for hardware with problematic codec semaphores buggy_semaphore 0

Now,
these options are all able to be given a numerical value, first question, what do they stand for and what does the value do?

and second question, does anyone know what a semaphore is in relation to audio codecs? I have worked with audio for years and never some across this termanology???

Any help would be of most help!

Stewart

I don’t have specific answers to your question.

There are some general descriptions to some of the terms you quoted in the alsa-configuration.txt file that comes with the alsa driver documentation. Here is a link to an older version: Linux Kernel Documentation :: sound : alsa : ALSA-Configuration.txt

Are you certain these are relevant to your distorted audio ?

Can you confirm that you are running oS-11.2? If you have 11.1 then there’s a slew of updates (audio issues were common when first released).

Once this is done, the audio quality is still fairly awful, but doesn’t sound like my guitar’s fuzz box!
<snip>
Now,
these options are all able to be given a numerical value, first question, what do they stand for and what does the value do?

Fraid though I have an Nforce2 based board, it uses Realtek HD audio, and “just works” providing a very different set of tweak options. These are hardware specific config options which enable workrounds.

For moment I would think it unlikely you need one, AC 97 normally works out the box, without issue. If Nforce2 AC97 does need something, it’ll have turned up before. If you can provide more hardware details (the log file /var/log/boot.msg contains hardware recognition), it can help see if there’s a known workround for your problem.

and second question, does anyone know what a semaphore is in relation to audio codecs? I have worked with audio for years and never some across this termanology???

Presumably in context it’s an OS style Semaphore, used to coordinate access to some limited shared resource in this case likely audio output channel.

Same problem here. I’ve installed 11.2 on a A7N8X-X board that uses AC97 and the sound is horribly distorted, regardless ALSA or pulse audio.

I’ve tried tweaking the stuff in YAST but no results.

Are you a gnome user? I find gnome’s pulse audio implementation is rather poor and it introduces distortion. …

There are various fixes noted here that you could try in step-7:
SDB:AudioTroubleshooting - openSUSE - step-7

in particular you MUST try the suggestions in the links to that link (step -7): PulseAudio - openSUSE On one of my PCs I found in Gnome this worked for me:

Glitches in audio playback

Edit /etc/pulse/daemon.conf: uncomment the default-fragments and default-fragment-size-msec, and change values from the default 4 and 25 to 16 and 21.