KDE causes conflict with soundcard?

[redss]

I have a remastered compactflash version of knoppix 3.4

When I boot knoppix, my onboard soundcard (AC-97) is recognized and configured (using OSS, not ALSA). If I boot into single user mode, my soundcard is functional, since typing the following command at a prompt enables me to hear something:

cat file.au > /dev/dsp (also I can redirect to /dev/audio)

However, once booting into KDE 3.4, the soundcard is no longer accessable. typing the above command at a prompt returns "device or resource busy"

How can I keep KDE from causing a conflict with my soundcard?

[saikee]

Using a more recent Knoppix should help. V3.4 is in dark ages when comparing with V5.1.1. Older Knoppix are painfully slow. Modern Knoppix and many other distros run satisfactorily on USB devices without the need of being re-mastered..

[redss]

Please, I don't need that kind of answer. I spent weeks remastering knoppix3.4 to compactflash and I can't start over every time there is a new version out.

My version 3.4 will work, I just need to find out what is causing the conflict.

[retsaw]

Your onboard sound card seems not to support hardware mixing so only one program can use it at a time. There are some sound servers which are intended to work around this problem, the downside is anything that wants to play audio needs to go through the sound server rather than access the sound card directly.

In this case it is likely that KDE's sound server, aRts, is running and blocking your sound card. You should be able to disable it by going into the KDE Control Center -> Sound & Multimedia -> Sound System.

It may be to your advantage to upgrade, since a new kernel likely supports your sound card with ALSA which has software mixing in the form of dmix, which works transparently for ALSA supporting programs and is a much better solution than using a sound server.

As for remastering Knoppix being timeconsuming, maybe you should try a different distro such as SLAX (http://www.slax.org/) which is modular in design and much easier to remaster than Knoppix, you could have a standard base which you can upgrade easily and a separate module with your customizations that you keep the same.

[redss]

Thanks for your reply.

The checkbox "enable sound system" was not checked, and when I check it, it says "can't initialize, /dev/dsp was busy, using /dev/null instead".

The question is, why is /dev/dsp NOT busy before booting into KDE?

[retsaw]

Tryfuser -av /dev/dspHopefully that will tell you which process is using it.

[redss]

That did it! The fuser command revealed that 3 processes called ogg123 were trying to play the startup.ogg file. Kill -9 on the first process freed up the audio device. I wonder why that ogg123 process got hung?

[redss]

Found the problem. The fuser command revealed that 3 processes called ogg123 were trying to play the startup.ogg file. Kill -9 on the first process freed up the audio device. I wonder why that ogg123 process got hung...