[PlanetCCRMA] Problem with Jack?

Fernando Pablo Lopez-Lezcano nando@ccrma.Stanford.EDU
Tue May 13 10:20:02 2003

> I am sorry if I'm covering old ground here. I have recently configured
> my system with all of the Planet CCRMA packages (running RH 8.0 on an
> AMD processor with on-board via82xx sound). All packages appear to work
> properly except Jack. When I run Jack in a terminal I get a screen of 
> **** alsa_pcm: xrun of at least 0.0xx seconds
> When Jack runs as such, I can get ardour to work, but when recording
> from the pcm source, there is a lot of noise. I have not been able to
> get rid of this noise by turning off different channels on the mixer.
> The noise is heard whenever I turn a track on for recording. I have no
> problem recording with Audacity or Cinelerra,

They are using oss emulation over the alsa drivers and most probably use
a lot more buffering than the default for jack. 

> so I think the problem is
> with Jack and not with Alsa or my hardware. I have not identified any
> IRQ conflicts.

Did you go through the web page on optimizing for low latency? If so,
there's not much to do except raise the number of periods per buffer or
the size of the buffer in jack (but that will, of course, raise the

-- Fernando