Trying to get Jack and soundcard running properly

Installation & Configuration Linux
#1

Hi Folks

I’ve recently installed Ardour and Jack and I’m a bit of a novice at sound recording so please bear with me. I’m running Ubuntu ‘Gutsy’ on a Dell inspiron 6400 with an on-board Intel sound card. I’ve got a Tascam US-122 audio interface connected to it via USB.

I’ve got sound (from a mic) into Jack and out to Ardour. However, the sound signal is cracking up. Looking into Jack I get the same problem even if when the only connection I make is between alsa_pcm > capture_1 and alsa_pcm > playback_1.

Looking at the messages I found this:

**** alsa_pcm: xrun of at least 0.031 msecs
**** alsa_pcm: xrun of at least 0.035 msecs
**** alsa_pcm: xrun of at least 0.033 msecs
**** alsa_pcm: xrun of at least 0.024 msecs
**** alsa_pcm: xrun of at least 0.024 msecs
**** alsa_pcm: xrun of at least 0.018 msecs
**** alsa_pcm: xrun of at least 0.044 msecs
20:04:27.346 XRUN callback (11 skipped).
**** alsa_pcm: xrun of at least 0.026 msecs
**** alsa_pcm: xrun of at least 0.020 msecs
**** alsa_pcm: xrun of at least 0.027 msecs
**** alsa_pcm: xrun of at least 0.026 msecs
**** alsa_pcm: xrun of at least 0.025 msecs
**** alsa_pcm: xrun of at least 0.027 msecs
**** alsa_pcm: xrun of at least 0.063 msecs
**** alsa_pcm: xrun of at least 0.033 msecs
**** alsa_pcm: xrun of at least 0.034 msecs
**** alsa_pcm: xrun of at least 0.030 msecs
**** alsa_pcm: xrun of at least 0.031 msecs
**** alsa_pcm: xrun of at least 0.043 msecs
**** alsa_pcm: xrun of at least 0.030 msecs
**** alsa_pcm: xrun of at least 0.030 msecs
20:04:29.382 XRUN callback (13 skipped).
**** alsa_pcm: xrun of at least 0.039 msecs
**** alsa_pcm: xrun of at least 0.051 msecs
**** alsa_pcm: xrun of at least 0.031 msecs

Now I’m sure this makes sense to some of you guys but it beats me, although I’m guessing that it may well have something to do with the problem. I’ve played around with some of the settings in Jack but although I can alter the signal quality to a degree, it’s far from perfect.

Any help really appreciated. I just wanna lay down some tunes…

cheers
darin

#2

Hi Darin,

I also use a US-122 with a Dell Inspiron 9400 and Ubuntu Gutsy. It works very well, Some suggestions:

-Is the mic/line switch on your US-122 set for “mic”, is the red clipping indicator lighting up as you record?

-Make sure you have the Ubuntu Realtime Kernel Installed, Open Synaptic and Install the “linux -rt” package

-Check out the excellent Audio repository at http://archive.ematech.fr/ it has updated packages for Ardour and most importantly JACK 109.2

-Ematech also has the latest alsa-firmware package for your US-122

-JACK setting for the US-122 should be 512 frames per period with 3 buffers, make sure you have properly selected the US-122 in the JACK setup dialog

Hopefully that should get you started, Post back if you have further difficulties.

#3

Thanks GMaq!

Changed the buffer frames settings as suggested and am now up and running. Will implement the other suggestions too.

Again, many thanks

darin