After upgrading to KDE 3.2.1 I get the following message on startup of KDE as a user:

Sound server informational message:
Error while initializing the sound driver:
device: default can't be opened for playback (Permission denied)
The sound server will continue, using the null output device.

If I start KDE as root the sound works fine. As a user I can play MP3 files also, but I don't get the startup sound that KDE makes. So I know it is not a configuration problem with my sound card.

I realized this was a permission problem. Yeah the "Permission Denied" part was like a flashing neon sign. So initially I tried to change the permissions on /dev/dsp0 & /dev/midi00 & /dev/mixer0. That didn't work so I changed them back to their original permissions.

Then I decided that maybe their was a group for audio or something. So I sent into /etc/groups and looked for something. Nothing looked obvious to me that would cure this issue.

My question is how/where do I change permissions out to get this to work as a user?

Using Slackware 9.1, the only thing I have changed from the default install is KDE 3.2.1 upgrade.

Yes, I am new to slackware.

Thanks for any help.

I had that when i upgraded kde.

From memory(?) you have to do (as root obviously)

chmod 666 /dev/dsp*
chmod 666 /dev/mixer*

to allow all users access to sound.

I tried changing those permissions. It still gives me the same error. I previously tried a

chmod 777 /dev/dsp and other relevant /dev files

I tried the 666 flag too, just to make sure. Did not work.

Thanks for the reply though.

did you remember the * wildcard so all relevant files are changed?

Yes, I was careful to include that portion.

I guess I should add I am coming from FreeBSD to Slackware so I do have some experience. The most annoying part of this is I had a similar problem in BSD, but I can't recall how I fixed it. It may not be the same in Linux anyway.

Edited: Spelling error.

try

Tried that and I received a message like:

-user silverback011 already exists; please choose another Login name for new user[]

So, I guess there is no audio group.

Must be a formatting mistake. There has to be an audio group if you can get sound as root. Hmmm. useradd? Does Slack have a user-configurator?

Not that I am aware of. I tried the user manager built in with KDE (KUser). I usually don't like these tools..... It didn't show a audio group. I didn't see one in /etc/groups either.

I can live with this. I just can't use that cool "You've got mail!!" sound effect in KDE. However, I can still use my mp3's. I thought this would be an easy fix.

Could this be related to the permissions set on the arts driver?

I think you hit on it. If you can hear mp3s then you are part way there. Whatever you are listening to your mp3s with must not be using aRTS, I bet. If you want to try and get that message to stop, you have a few things you can try. If you go into the KDE control panel and select the sound system, you have the opportunity to turn it off, which should stop the permissions dialog to pop up. Or, you can try with other devices. Under the hardware tab, try using a device other than aRTS. For example, if you're using ALSA, try that. Good luck.

Add the user to the sys group and reboot. That works for me when I use aRTS and ESD.

Thanks to everyone for their help.

The problem is fixed now.

I added the user to the group 'sys' as Ninja Cow suggested, and now aRTS works. Never would have thought that 'sys' included sound system.

Ninja Cow....reminds me of a character in a really bad B-Movie named "Kung Pao". I really liked the fighting cow scene. Any chance that is where your handle originated?

... and wich devices or other kind of files need sys group to be used or altered ? You're right, be member of sys solved the problem but at what cost ?