[linux-audio-user] [JACK Fwd: strange-difficult to explain BUG]

MarC marc_contrib at ramonvinyes.es
Tue Dec 21 16:17:05 EST 2004

I posted that message to the JACK list.
Anybody has the same problem?
sbdy at the JACK list said that it disappeared with kernel 2.6.10...
I have not tried this (I'll wait for the package) but I find it strange.

-------- Missatge original --------
Assumpte: 	strange-difficult to explain BUG
Data: 	Sun, 19 Dec 2004 17:14:24 +0100
Respon a: 	
A: 	jackit-devel at lists.sourceforge.net

>I first though it was Ardour but then I realised that I could 
reproduce it under XMMS with the jack plugin....
When running jackd and using audio applications, after some time (for 
example 5minutes but not always the same time), I start listening a 
strange noise added to the music, then it stops, it comes again later 
but after a lot of time and like this until the end of the world.

>I have recorded this noise, recording the PCM output.
you can download it under the following link:

>note that the noise is not additive, it distorsionates the music 
(during the silence between tracks you cannot listen it, even if it 
started already in the previous track)

When I hear the noise, if I switch to the ALSA plugin, I can hear the 
music OK; but if I switch again to jack it the noise continues. The 
noise stops spontaneously after some time (1minute?) independently of 
the fact that I listen to music or I don't play anything. When the noise 
stops Jack displays in the message window: "**** alsa_pcm: xrun of at 
least 0.058 msecs". This is normal?????

>Here there are some specs of my system:

I am running the last version of jackd under Debian testing: 0.99.0-2

with parameters (through qjackctl):
/usr/bin/jackd -R -p60 -t5000 -dalsa -dhw:0 -r44100 -p512 -n2 -S -i1 -o2

(short latency: 23.2ms)

with an audigy card, with a kernel 2.6.8 + realtime module

my fstab is the following one:
maybe this explains why I am the only one (i didn't hear of anyone) 
complaining about this bug?

sh-2.05b$ more /etc/fstab
# /etc/fstab: static file system information.
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults        0       0
/dev/sda8       none            swap    sw              0       0
/dev/sda5       /               ext3    defaults,errors=remount-ro 0       1
/dev/sda6       /home           ext3    defaults        0       2
/dev/sda2       /winsegur       vfat    rw,user,exec,codepage=850,umask=000
0       0
/dev/sda1       /winxp          vfat    rw,user,exec,codepage=850,umask=000
0       0
/dev/hda        /media/cdrom0   auto    ro,user,noauto  0       0
/dev/hdc        /media/cdrom1   auto    ro,user,noauto  0       0
/dev/fd0        /media/floppy0  auto    rw,user,noauto  0       0
/dev/sdb1       /marc           vfat    
00      0       0
/dev/sdb2       /home/marc      ext3    noauto,user,exec        0       0
/dev/sdc1       /media/usb0     vfat    
00      0       0

>It's quite annoying because this stops me to use Ardour to play live 
Anyone that can help me?

P.D: the music is from the album Wave of Antonio Carlos Jobim :)

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