Originally posted by Lord Zoltar
I can run XMMS, Noatun, Kaboodle, anything, and I can't hear the MP3's. Noatun looks like it's working: the visualizer starts visualizing the song, etc
This is consistent with your first error message:
The sound server will continue, using the null output device.
So, aRTs is in fact running, but is directing the output (the sound) to a "null output device", which means you can't hear it (as your sound card and speakers are real devices, not null devices).
Noatun, Kaboodle and JuK are using aRts automatically, because they are integrated with KDE. XMMS is using the wrong output plugin (and your sound card may not be properly set up), so it gets confused before giving up (and probably also outputting to null, since if it really can't play anything, it either crashes outright, or gives you a message along the lines of "I can't play; check your output plugins, or see if your sound card is borked and make sure no other program is blocking sound output").
The fact that audio CDs play is not all that helpful insofar as audio CDs use raw device access and don't go through the same channels as sound files on your HDD, but it does at least indicate that the sound card and speakers themselves are not broken (and that the CD channel at least is not muted).
The first thing I would suggest is that you go to the KDE Control Center=>Sound and Multimedia and set your aRTs output plugin from the default (Auto-Detect), which does not seem to work, to ALSA --if you have actively installed ALSA, since this is Slack 9.1, which still used the 2.4 series kernel and thus does not have ALSA integrated-- or to OSS, if you have not installed ALSA (which I suspect-- or at least that you have not installed it fully).
Also make sure that "Enable sound server on startup" is checked (which it should be by default, and most probably is, since the sound server is attempting to start at KDE startup).
Then log out and back in and hopefully the initial error will be gone. However, you may get another
error telling you that one or more of the specific mixer devices cannot be opened (most commonly /dev/dsp). In that case, I usually take the easy way out and hack /dev/dsp 's permissions in a root terminal or file manager (but the "recommended" way to solve this is to add your user to the group which is allowed to use /dev/dsp, commonly the "audio" group. But distros are different from each other, and I usually don't feel like hacking around to find out what group the particular distro I may be using calls the audio group. Or I am in the audio group, but it's still giving me that error). But this assumes that you have already correctly installed and configured ALSA, which may not be true in this instance.
Even this may not work, and you still may not have sound in audio apps. If, at any point in this process, you have sound in Noatun and Kaboodle, then just do as adz
said and get the aRTs plugin for XMMS, or if that's not available, recompile XMMS from source (this is
Slackware, after all; you can compile anything and everything) and follow whatever instructions may be in the README or INSTALL files to enable KDE support. Or just use Noatun and Kaboodle as KDE intends, because you're done.
If you still don't have sound, it's on to the last two possible issues: the Muted Mixers, or Incomplete Install of ALSA.
The mixers first.
ALSA mutes all mixers by default. Don't ask why; we don't know. New users don't realize this, and think that their sound card is not working, when in fact the problem is that the volume is essentially at "0". So, let's check that out.
Open a terminal and type alsamixer
. If you don't have it, we know then that the problem is in fact an Incomplete Install of ALSA; skip then to the next part and come back here when ALSA is installed. In the "non-gui" alsamixer, use the left and right arrow keys to move through the various mixer channels, use the "M" key to unmute them, and use the up and down arrow keys to raise the volume. Don't raise the volume over 90% or so, otherwise you'll probably get distorted sound. In the pretty gui alsamixer, you can mouse around and click little LED icons to do the same thing. The gui alsamixer (which I still don't know how sometimes I get that, but usually don't) may have a specific "Save" menu option, or it may not. Don't remember, sorry.
After you have unmuted the alsamixer, you should also run KMix (the KDE mixer program), to raise the volume levels in aRTs itself (or something-- the Desktop Environment mixers are related to the ALSA mixers, but changing one of them does not necessarily change the other, for some reason).
If this was your problem, you will have sound from all correctly configured apps (see above for correct configuration of apps), and you're done-- but only for this session. Saving and restoring the mixer settings must be done at shutdown and bootup; this is usually handled by an initialization script which automates this process. Check the Slackware Essentials Book
if you don't know where this script is or how to add it to your default runlevel.
If you don't have alsamixer, or received some error that indicates that the sound card was not found, you most likely have an Incomplete Install of ALSA. A complete ALSA installation consists of several packages: alsa-driver
(which you do have, as the driver modules are in fact loaded), alsa-libs
(for OSS emulation, optional but highly
(which contains alsaconf to configure the soundcard, alsactl to store and restore mixer levels, and alsamixer to set the mixer levels in the first place), alsa-tools
, and alsa-firmware
. At the very least, you must install alsa-driver, alsa-libs, and alsa-utils... and in that order (as they depend on each other in that order). You definitely have alsa-driver installed (if you have upgraded to a 2.6 series kernel, alsa-driver is integrated with the kernel itself), but you may need to install alsa-libs and alsa-utils (which are not included with the 2.6 series kernels, but are still necessary), after which you could run alsaconf
to configure your sound card, and/or follow the instructions on the ALSA Details page for your specific sound card
(which I know what it is, because I have VIA8233 onboard sound as well, and you've loaded the same driver as I use), or refer to the Slackware FAQ
I think that pretty much covers it... one way or another, sound should be working after all this. Hope it helps, and good luck.