[Pkg-alsa-devel] Bug#736512: Bug#736512: alsa-base: Creative Labs CA0106 Soundblaster captures broken audio, unless same program is using any alsa device for playback

[Elimar Riesebieter]

* Nikolay Shaplov (Swami Dhyan Nataraj) <dhyan at nataraj.su> [2014-01-24 16:39 +0400]:

> Package: alsa-base
> Version: 1.0.25+3~deb7u1
> Severity: normal
> 

> Dear Maintainer,
> 
> I have Creative Labs CA0106 Soundblaster (PCI: 1102:0007,
> snd-ca0106)
> And it does not work properly on audio capture in a very strange
> way:
> Ones I try to capture some sound it gives me a result broken in a
> way shown in attached file (there I slowly says "1 2 3 4 5")
> But if I use audacity for capturing and there are other tracks
> that is played back while recording, sound captures well.
> Play back can use the same device, or another, it does not matter,
> if playback is on, capture is good. So I consider it is not
> snd-ca0106 module problem, or not only the module problem.
> If I start playback with another program (i.e. vlc) and start
> capturing with audacity without playback, then captured result is
> also broken.
> So I consider that it works only when playback takes place in the
> same alsa session (or whatever it should be called)
> Do you know anything abut such issues? I can provide more info or
> do other exploration if you tell me where to explore.
> 
> -- Package-specific info:
> --- Begin additional package status ---
> Desired=Unknown/Install/Remove/Purge/Hold
> | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
> |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
> ||/ Name                                       Version                    Architecture               Description
> +++-==========================================-==========================-==========================-=========================================================================================
> ii  libasound2:i386                            1.0.25-4                   i386                       shared library for ALSA applications
> --- End additional package status ---
> --- Begin /proc/asound/version ---
> Advanced Linux Sound Architecture Driver Version 1.0.24.
> --- End /proc/asound/version ---
> --- Begin /proc/asound/cards ---
>  0 [PCH            ]: HDA-Intel - HDA Intel PCH
>                       HDA Intel PCH at 0xf7f10000 irq 44
>  1 [CA0106         ]: CA0106 - CA0106
>                       Audigy SE [SB0570] at 0xd000 irq 17
> --- End /proc/asound/cards ---

Your default card is a HDA-Intel?

For your soundblaster I found a hint at [0]: 

"Not all features on all models supported. On the VX, white noise on playback
unless initialized in Windows first. One quirky (but permanent) workaround is
to enable the old oss modules, specifically the 100% sound blaster compatible
module (sb). You don't have to load the oss modules. The alsa module snd-ca0106
works fine somehow if the old sb module is compiled in the kernel as a module
(no white noise)."

You`re running stable. So your drivers are provided since ages and there is no
bug reported like yours, though. I don't have a CA0106 based soundcard handy,
so I can't reproduce..

[0] http://www.alsa-project.org/main/index.php/Matrix:Vendor-Creative_Labs

Elimar
-- 
  Do you smell something burning or ist it me?