I have installed Slackware 9.0 on a Compaq Armada 1530DM laptop and got the built in sound hardware to work by using the SoundBlaster drivers found in rc.modules (from what I have read, the audio hardware should be 100% SB compatible).

I installed by doing a minimal install (text only) and did expert selection, and I was pretty picky with the packages (small HDD) so it is possible I just missed a package, in which case I hope somebody knows which one.

Anyway, the problem is that while I can play audio CDs, I can't seem to play any audio file. I have tried "amp" and "mpg123" and I can't play MP3s, or WAVs. There are no errors, and the programs both say that decoding completed, so from what I can tell they play the file, there is just no sound being generated.

I have no problems accessing the mixer from "rexima", and all the volumes are up.

It also doesn't matter which user I am, since it doesn't work as root either.

What could be the problem?

try mpg321. that worked for me once when amp didn't.

mpg123 and mpg321 are the same thing.

I was thinking it may be a libao issue, since the first time I didn't install it, and it gave me errors. I installed the Slackware package that included it, and later downloaded the latest version, but didn't help.

Does anyone have a libao.conf, and if so, what is in it?

well, they're not exactly the same. mpg321 is open source and uses different libraries, while afaik, mpg123 is not open source.

you might need the libao development libraries:
http://www.xiph.org/ogg/vorbis/download/

i don't think you need a libao.conf. I never touched it and i have still been able to play mp3s with xmms on any linux or bsd i have used. try installing libmikmod , libaudiofile to see if it gets any better.

Libaudiofile isn't a Slackware 9.0 package, but there is a audiofile lib, which is already installed. And libmikmod is a GNOME XMMS, so that wouldn't be needed.

I have booted the same machine with a Slackware LiveCD (SLAX) and it can play MP3s with mpg123, so hardware doesn't seem to be the problem. It also had all of the same sound modules loaded under the LiveCD as it does under the normal system, though a few were "(autoclean)" on the LiveCD.

I have found out that mpg123 is using "/dev/dsp" to play audio files, changing this to use "/dev/mixer" causes an error saying the device may be busy. Is this normal?

check the rights on theses devices first...change them if necessary

Already did, but like I said, the problem persists even as root.

Possibilities: Could this be a hardware issue? Are you using headphones that are plugged into the CD player instead of the soundcard? Are the speakers turned on? Are you sure that the file itself is audible? (Is the same MP# or whatever playable under Windows)? -- J.W.

As I said before, I booted the machine with SLAX and played the same MP3, and it worked fine.