Hi,

This thread is not about how can I get my sound working(For most part of it
), rather I have my sound working(after loads of reading & research) but I would like to know something things related with sound so that my fundamentals are clear. My question is a bit long but I guess it will be useful to other people to get some idea of how to get their sound card working.

So here is my question.

I am using debian kernel 2.6.16(testing) which I configured to compile the sound driver for my sound card (National Semi-Conductor CS5535) as a module(snd-cs5535) under ALSA. Also I left the OSS support also in there as a module.

Now, after loads of reading, I heard that ALSA is a replacement of OSS and I one should either use anyone of them i.e. either ALSA or OSS.

So, after I booted into my compiled kernel and during the boot it said that snd-cs5535 loaded successfully and I did the following:
#apt-get install alsa-base alsa-utils alsa-oss alsamixer alsamixergui

Then I did
#alsaconf

but after rebooting my system after running alsaconf, I had problem loading my sound card driver. It said something like "modprobe snd-cs5535:Unknwon parameter 'index' found" during the boot up.

So I uninstall alsa-base
#dpkg -i alsa-base

and then booted again and this time it said that my sound card module was loaded successfully.

Now again I was still not able to play the sounds. so I read more and then I tried:
#alsamixer

and to my delightment I found that the only problem was that my Master and PCM channel were muted... So I unmuted them and viola I had my sound in the xmms player. My XMMS player is using the ALSA output driver under Preferences.

Also, I read somewhere that it would be a good idea to install udev also.
So I did
#apt-get install udev

But there was not sound in gnome applications. So I decided to test the sound in some other player(other than xmms) so I downloaded the madplay
#apt-get install madplay

and I did

#madplay -v test.mp3
and it gave it error:

Device /dev/dsp not found.

Then I read more and found that OSS driver uses /dev/dsp device file. SO I did:
#modprobe snd-pcm-oss

And I had my sound in madplay also. But still there was no sound in GNOME. So I added the following line in my /etc/modules
#modprobe snd-pcm-oss

and rebooted my system. And guess what my GNOME sound was there!!!!.

So I have two questions:
1.How come my system is using ALSA and OSS(for gnome application) both? Or is snd-pcm-oss is a part of ALSA driver and it is just an OSS simulation. I think I read it somewhere about OSS and also all the sound driver which starts with 'snd' are ALSA drivers. So if snd-pcm-oss is infact an ALSA driver then my question gets answered automatically.

2. Generally people say to run alsaconf to get the sound card configured. But in my case it was other way round. Running alsaconf gave me trouble loading the sound card driver module(see above for details). How do you explain this?


I will really appreciate if some one can throw some light as to what is going on?

Thanks in advance.

1. OSS was the old sound driver. ALSA replaced it on most distros since it has better sound quality and more futures. On the downside, not everything already supports ALSA and it can be very hard to configure for some apps (including some popular games). Therefore the OSS emulation, so you are correct about "snd-pcm-oss", it provides OSS emulation for the kernel.

2. "alsamixer" shoudn't be able to do anything without first doing "alsaconf" (it creates the needed configs). My only guess is that it actually did work even though it gave you that error... alsa-base wasn't needed in the first place.

Thanks Jens!!! Excellent......

Regarding your reply of "alsa-base wasn't needed in the first place" , I did not understand why it was not needed? Was it not required because as I said earlier that initially my driver loaded fine even without installing alsa-base/utils.

Also how can we know if alsa-base is required or not? Is alsaconf a part of alsa-base or alsa-utils??

Should I just have installed alsa-utils?

alsa-base Is just part of an other way to configure it (using either the alsa-source package or a pre-configured alsa kernel module in dep form).

I think "apt-get install alsa-utils" comes indeed with all needed dependencies.

PS: If you ever have a program that doesn't work or acts funny(like Doom 3) with alsa, you can force it to use OSS by adding "+set s_driver oss".
example:
./doom3-demo +set s_driver oss