Hi,

I am having a HARD, PARTIAL FAILURE OF SOUND on my Linux system (Slackware 13.1, the latest, with a 2.6.33.4-smp kernel and KDE 4.4.3). The failure is "HARD" in the sense that once it occurs it remains broken until I reboot the system. It's a "PARTIAL" failure in that it affects ONLY SOME sound software on my system. Here is a list of what fails and what doesn't. (I'm sure there are other programs I could use to test with, but I don't know what they are since I am "just an average user" when it comes to multimedia software.)

These don't fail:

Amarok
KDE event notification

These do fail:

Firefox
Xine
Mplayer

In the things that fail it is only the sound portion of whatever (flash, mp4, etc) which goes away; the video portion plays normally.

I leave my system up for days at a time. The failure occurs some "long-ish" time (days) after I reboot. I have no idea what triggers it. I do not use sound most of the time, but when I do it's music through Amarok (which doesn't fail) so I do not notice the failure when it occurs.

It seems clear to me that it is NOT the failed programs which are at fault but it is, rather, some underlying set of sound libraries and/or servers used in common by all the programs which fail, and that the failure occurs when something happens which affects that set of sound libraries and/or servers.

I don't think this is specifically a Slackware issue since I've seen a few other problem reports on the web where the sound simply stops on non-Slackware Linux systems. Some of the problem reports I've seen suggest that playing sound from one program stops sound from other programs. I've tried various combinations of sound-producing programs but none have triggered the problem.

I've looked at /var/log/{messages,debug,syslog} and see nothing relevant. I've gotten process lists from ps before and after the failure and no "relevant" processes have gone away. (But note, as before, that I am NOT a Linux "multimedia guy" so I can only make intelligent guess at what is "relevant".)

Does anyone know what this problem is and, better still, how to solve it? Or where I could look for additional clues? Is there some way to "reset" the sound system without having to reboot?

Help.


Thanks in advance,
Jeff B

Some applications initially mute the volume, in case some guy starts playing a porno video, and his mom is in the next room. So, check the volume control and make sure everything is working with that. The system might also be switching between different sound systems (alsa, jack, pulse), but only one of them is configured for the system. AND, if I were a self respecting slack junkie, I sure a h*** wouldn't use sound.

>> Some applications initially mute the volume

I've checked that too, and it is not the problem.

>> if I were a self respecting slack junkie, I sure a h*** wouldn't use sound.

Good thing I am not a "slack junkie". Junkies of all types have no self-respect. I use Slackware Linux for everything that I can get out of it and have no problems with my self-respect.


Anyone else have any ideas as to why my sound system just stops working until I reboot?


Thanks

I have found the trigger for this problem. It happens when I do a "Switch User" under KDE. This is a reproducible error. It seemed random before because I am the one to log in after a reboot, so everything works initially, but at some later date my wife logs in via "Switch User" to read her eMail, and the sound is gone after that.

It doesn't matter which user I switch to (myself, my wife, root), the sound from the original session quits sometime just after the new session's desktop appears. The affected programs under the new session have no sound. When the new session logs out and I go back to the old session, the sound stays gone.

Anyone have any idea who I should complain to? This is an inter-system bug between whatever sound software the affected programs use and KDE or something KDE runs.

I've found a work-around for this problem. I manually run the following on the command line:

/usr/sbin/alsactl init

after I return to the original session. I do not need to be root to run it. Having to do this is a pain the ass but it's less work than rebooting et al. Running this command initializes the ALSA sound system and the applications which were silenced by the "Switch User" are now able to produce sound again.

This is still a bug which needs to be fixed.

I don't know if it's the same problem but I have the same Slackware version with XFCE.
I also have issues with sound getting unavailable.
It goes like :
I play music on Amarok.
I have some other applications potentially needing sound running : Firefox, video game, teamspeak.
I select another track on the playlist on Amarok... so it basically stops playing, then restart with another file.
There it is : The track goes as if it was playing sound but I do not hear anything.
I have to shutdown Amarok and any other applications that use sound mentioned above, then restart amarok and then restart the other applications back.
I'm having the issue right now and the command you gave returns :
The sound is still available in firefox and WoW but the volume is lowered...