[PlanetCCRMA] Jack crackle...

[David Fraser]

Fernando Pablo Lopez-Lezcano wrote:

>>>>>>Generally, but there are different ways to write to soundcards under ALSA,
>>>>>>and jack uses a particular one. Or something like that - I'm a bit hazy on
>>>>>>the details :)
>>>>>>
>>>>>>            
>>>>>>
>>>>>I'm using the same "card" without any of the described problems...
>>>>>
>>>>>          
>>>>>
>>>>Interesting, what driver are you using for it?
>>>>
>>>>        
>>>>
>>>Same as you, snd-intel8x0. What gives "/sbin/lsmod",
>>>"more /proc/asound/version" and "more /proc/version" ?
>>>
>>>      
>>>
>>I've put the relevant output of these below ... (do I need more from lsmod?)
>>I also have been having problems with jack sometimes producing silence 
>>... restarting jack sometimes fixes it, sometimes not.
>>Through this though I did notice that I had newer versions of alsa-libs 
>>and alsa-utils than the rest of alsa...
>>but changing these to the same versions (latest from ccrma) did not 
>>affect the problem...
>>
>>[root at scir bin]# lsmod | grep snd
>>snd-seq                47632   0  (unused)
>>snd-intel8x0           23460   3
>>snd-pcm                87392   2  [snd-intel8x0]
>>snd-timer              20068   0  [snd-seq snd-pcm]
>>snd-ac97-codec         50712   0  [snd-intel8x0]
>>snd-mpu401-uart         5256   0  [snd-intel8x0]
>>snd-rawmidi            19008   0  [snd-mpu401-uart]
>>snd-seq-device          6332   0  [snd-seq snd-rawmidi]
>>snd                    44676   1  [snd-seq snd-intel8x0 snd-pcm 
>>snd-timer snd-ac97-codec snd-mpu401-uart snd-rawmidi snd-seq-device]
>>soundcore               6500   0  [snd]
>>snd-page-alloc         10356   0  [snd-intel8x0 snd-pcm]
>>[root at scir bin]# cat /proc/asound/version
>>Advanced Linux Sound Architecture Driver Version 0.9.6.
>>Compiled on Sep 11 2003 for kernel 2.4.20-20.1.caps.rh90 with versioned 
>>symbols.
>>    
>>
>
>This is quite old... both the kernel and sound drivers. Current
>planetedge version is:
>
>  
>
>>cat /proc/asound/version
>>    
>>
>Advanced Linux Sound Architecture Driver Version 1.0.3.
>Compiled on Feb 29 2004 for kernel 2.4.25-1.ll.rh90.ccrmasmp (SMP) with
>versioned symbols.
>
>(or kernel 2.4.20-30.1.caps.rh90.ccrma for the capabilities enabled
>RedHat kernel). 
>
>  
>
>>[root at scir bin]# cat /proc/version
>>Linux version 2.4.20-20.1.caps.rh90 (root at cmn19.Stanford.EDU) (gcc 
>>version 3.2.2 20030222 (Red Hat Linux 3.2.2-5)) #1 Wed Sep 10 12:51:47 
>>PDT 2003
>>
>>[root at scir bin]# rpm -qa | egrep '^alsa'
>>alsa-utils-1.0.2-2
>>alsaplayer-0.99.76-1.rhfc1.ccrma
>>alsa-driver-1.0.1-1.cvs.rhfc1.ccrma
>>alsa-patch-bay-1.0.0-1.rhfc1.ccrma
>>alsa-kernel-2.4.20-20.1.caps.rh90-0.9.6-2.cvs.rh90
>>alsa-lib-1.0.2-2
>>alsa-firmware-1.0.1-1.cvs.rhfc1.ccrma
>>alsa-kernel-2.4.24-1.ll.rhfc1.ccrma-1.0.1-1.cvs.rhfc1.ccrma
>>alsa-lib-devel-1.0.2-2
>>alsa-tools-1.0.1-1.cvs.rhfc1.ccrma
>>jack-audio-connection-kit-0.94.0-1.rhfc1.ccrma
>>    
>>
>
>You seem to have a rather unorthodox mix of packages :-)
>
>alsa-utils, alsa-driver, alsa-kernel*, alsa-lib* and alsa-tools should
>all be the same version for best results. While a mix of versions may
>work we would never know if that is the problem. Let me guess, you are
>probably using freshrpms as well, which has a newer version of the alsa
>driver (but no kernel modules for the custom Planet CCRMA kernels). 
>  
>
Yes, good guess ... I fixed this but it didn't help...

>I would suggest upgrading to the latest kernel and kernel sound drivers,
>at least the previous paragraph output of /proc/asound/version suggests
>you are using a quite old kernel module set. 
>
>I you want to use the RedHat kernels you would need to:
>  apt-get install planetccrma-core-redhat
>for the capabilities enabled RedHat kernel or
>  apt-get install planetccrma-core
>for the Planet CCRMA kernel. 
>  
>
Thanks, I did this but it hasn't resolved the problem... (took me a few 
days to get to a point where I could upgrade my kernel.
Then had to deal with my proprietary nvidia network drivers :-)).
I now have kernel 2.4.22-1.2140.nptl.caps.rhfc1.ccrma and everything is 
consistent (alsa, jack, etc) with planetccrma.

>You will probably get conflicts, I don't know how apt will react with
>your mix of packages. Let me know and I'll help you navigate around
>them.
>  
>
Managed to sort out the package stuff, thanks. However somehow in the 
process my rpm database stopped responding ...
whenever I did anything with apt-get or rpm (even trying rpmdb 
--rebuilddb) I got the following error:
rpmdb: unable to join the environment
error: db4 error(11) from dbenv->open: Resource temporarily unavailable
error: cannot open Packages index using db3 - Resource temporarily 
unavailable (11)
error: cannot open Packages database in /var/lib/rpm

Well that had me worried, I was about to abandon RedHat/Fedora ...
But I have now discovered that setting LD_ASSUME_KERNEL=2.2.5 allows rpm 
to work.
So on I go...

>BTW, I don't think you mentioned trying different Jack buffer size (!=
>1024) and number of periods (> 2), did you do that?
>  
>
No this is interesting, and I have started trying to adjust these settings.
They definitely seem to affect the sound of the crackle, so it seems 
that this is the real problem.
However its a bit tricky playing around with the settings.
For example, if I set the rate to 44100, then I get a message that the 
playback rate != the capture rate
But I tried setting the rate to 48000 and when I tried to play a 44100 
rate file through XMMS, my system crashed.
I would presume that the greater the period * the number of periods (-p 
and -n) the less likely the crackle.
However, I haven't been able to find a combination that prevents the 
distortion, and it seems that p*n has a limit of 5120 or so.
Nothing I've tried in this range seems to work, and I get xruns of 
around 0.02 msecs repeatedly.
Anyway I'll keep on trying to change settings etc.
Thanks for the suggestions...

David