# ALSA changes in 2.6.21 ?

## pent0z

what is changed from 2.6.20 to 2.6.21 regarding alsa subsystem?

if i boot a 2.6.21 with the same .config of a 2.6.20 my audio card (even if at maximum volume from alsamixer) plays extremly low volume...

tryied with gentoo-sources (and viper-sources too, but i think that this is not the place to talk about unsupported kernels)

anyway with a 2.6.20 playing well

2.6.21-* (gentoo,viper) playing low

so i'm currently using 2.6.20-viper9 (i'd like to use 2.6.21...)

and yes, i've used alsamixer on every boot to assure that the maximum volume was selected... always low

----------

## tranquilcool

use alsamixer to set volumes then as root do

alsactl store and alsactl restore

----------

## RegularJoe

I have the same problem and the solution above did not work for me  :Sad:  Any other ideas?

btw I have SND_HDA_INTEL compiled in the kernel for my snd card which is:

```
Intel Corporation 82801G (ICH7 Family) High Definition Audio Controller (rev 02)
```

----------

## IvanMajhen

I have the same card as you. I didn't notice any regressions. Only good thing, such as mic boost. Maybe is your PCM setting low? 

I'm controlling volume and mute with front, don't know what is pcm for... it doesn't have mute

----------

## RegularJoe

 *IvanMajhen wrote:*   

> I have the same card as you. I didn't notice any regressions. Only good thing, such as mic boost. Maybe is your PCM setting low? 
> 
> I'm controlling volume and mute with front, don't know what is pcm for... it doesn't have mute

 

I checked everything like pent0z did so my volume levels are ok according to alsamixer. Generally I have the same problem as pent0z described.

----------

## dspgen

I had this problem also.  I compiled gentoo-sources-2.6.21 with the .config from 2.6.20, and no sound.

I went back to 2.6.20 for a few days.  Then today I tried 2.6.21 again, and it works fine.  I only use the optical out (Envy24PT/HT), so I never changed the volume on alsamixer - it has no effect.  

Don't have any idea why it works now.

----------

## IvanMajhen

Did you try passing modules option to driver, like modprobe hda_intel model=acer positionfix=1 or something like that?

----------

## cferthorney

If you run /etc/init.d/alsasound /restart what output do you get?  I have been battling with my sound for about a week now and yesterday I discovered a key module is missing (In my case snd-ioctl32) if you do a restart - does it mention anything about module failures?  It could be one of the OSS / ALSA modules which helps control volume is failing to load.

If it does fail to load the modules - check when it fails and search the alsasound script to see what is missing.

HTH

----------

## vonr

 *IvanMajhen wrote:*   

> Did you try passing modules option to driver, like modprobe hda_intel model=acer positionfix=1 or something like that?

 

That was the fix for me. Some things alsa (and especially hda-intel) related have changed, forcing autodetection on me. This has caused what the OP is describing.

Try setting "options snd-hda-intel model=auto" in /etc/modules.d/alsa.

----------

## cferthorney

 *cferthorney wrote:*   

> ... discovered a key module is missing (In my case snd-ioctl32) if you do a restart - does it mention anything about module failures?  It could be one of the OSS / ALSA modules which helps control volume is failing to load. ...
> 
> 

 

I stand corrected on this one - it turns out I needed snd-page-alloc - this seems to have disappeared from 2.6.21 .  I installed alsa-driver and compared the lsmod from this with an lsmod from my compiled kernel.  The only change was the alsa-driver version seemed to  include of snd-page-alloc.  I can not find this module in /usr/src/linux-2.6.21-gentoo/sound/core whereas in /usr/src/link-2.6.20-gentoo-r7/sound/core/ it does exist.

Any developers know why this module has disappeared from the gentoo sources kernel.  I downloaded a vanilla kernel for kicks 

```
ACCEPT_KEYWORDS="~x86" emerge --oneshot --ask --verbose vanilla-sources
```

 and there is a memalloc.c page  I haven't compiled the vanilla kernel, but as its to do with memory allocation I suspect it will produce snd-page-alloc.o and snd-page-alloc.ko .  

I seem to have gone off on a tangent here - but it may be that snd-page-allloc could be the change you've noticed?

*Edit - spelling correction*

----------

## dspgen

 *dspgen wrote:*   

> I had this problem also.  I compiled gentoo-sources-2.6.21 with the .config from 2.6.20, and no sound.
> 
> I went back to 2.6.20 for a few days.  Then today I tried 2.6.21 again, and it works fine.  I only use the optical out (Envy24PT/HT), so I never changed the volume on alsamixer - it has no effect.  
> 
> Don't have any idea why it works now.

 

Booted this morning (into 2.6.21), and sound doesn't work again.

Rebooted into 2.6.20, and it works fine.

strange.

What should I check next time I boot into 2.6.21 and sound doesn't work? dmesg, and what else?

----------

