[PlanetCCRMA] Soundblaster Live/ALSA drivers problem

Fernando Pablo Lopez-Lezcano nando@ccrma.Stanford.EDU
Wed May 21 18:09:01 2003


> I have installed the low latency kernel and ALSA driver RPMs, and run
> the ALSAConf script, which correctly detected my card.
> 
> Unfortunately, the results are currently terrible. The sound is weak and
> scratchy when I try to play audio files, and all in the left front
> speaker if I use line-in (rather like what you would expect under
> Windows if you had 5.1 speakers but had the audio settings set to 2
> speakers). It often gets faint and distorted over time.

What software are you using to play soundfiles?

> I can also hear faint interference in the speakers related to
> keypress/mouse movements at times (suggesting IRQ problems?).

It could be the video card swamping the pci bus and leaving no space for
the sound transfers (sympton is tiny clicks when you move the mouse
around), or it could be a more mundane ground problem where noise from
all the digital circuits gets into the output stages of the card. Hard
to tell. 

> I've messed around a bit with the alasmixer, but the settings don't
> improve the sound output. 
> 
> I've looked over some of the HOWTOs, but would appreciate some advice,
> as the point of installing the drivers this way was to get around most
> of these technical issues.
> 
> I am also confused about a few issues in the CCRMA instructions.
> 
> Firstly, is it necessary to use the updated kernel with the provided
> ALSA drivers? The notes seem to suggest it's optional, but I found that
> the ALSAconf script didn't seem to work until I booted the new kernel

Sorry if it is not clear. The alsa drivers must match (ie: be compiled
for) the kernel you are running. The current alsa drivers in the site
are built only for the Planet CCRMA kernel. You could use them with
another kernel but you would have to recreate the binary package for the
alsa-kernel rpm from the alsa-driver source rpm (while booted into the
kernel you are interested in running). 

> I
> only ask because I don't strictly need it on the machine I'm currently
> working on, and my TV capture card doesn't seem to like it for some
> reason. I mainly wanted the ALSA drivers for some game development, and
> wanted to preview the CCRMA stuff before trying it on a dedicated
> multimedia machine.
> 
> Also, the notes tell you to start the ALSA driver using
> 
> /etc/rc.d/init.d/alsasound start
> 
> However, if I do this, it tells me that the driver is already running.

It depends at what point you are trying to start it. If you rebooted the
machine then ALSA probably started when something in your setup tried to
use an OSS audio device (usually the sound server in the windows
manager). If that happens during the boot or login sequence then most of
alsa will get loaded automatically. 

> For this reason, I haven't done anything with chkconfig to make the
> drivers start automatically.

Just do the chkconfig step anyway. 
Sorry, but I'm not that familiar with the SBLive...
-- Fernando