Sunday, February 2, 2014

Getting MusE Working in Debian

  So I just bought a MIDI enabled keyboard and want to do have MIDI fun using MusE and my OS of choice, Debian (Knoppix).  Getting everything working just perfectly has been a real challenge, but I can now report complete success.

  So, the first thing you have to do after installing MusE it figure out why it's complaining about JACK not running.  qjackctl is the GUI frontend for jack, so running that and clicking 'Start' should make MusE happy. Unfortunately it's not that simple.  Jack will now complain that it cannot start in realtime and tell you to add some lines to /etc/security/limits.conf.  I added the following.
@audio           -       rtprio          99
@audio           -       memlock         unlimited
  You also have to add your user (knoppix in my case) to the 'audio' group. This can be done with
sudo usermod -G audio -a knoppix
  Now if you reboot at this point thinking that's it and you're done, you will be sorely mistaken, as evidenced by the command
ulimit -r -l
  The solution (and this was by far the hardest part to figure out) is to modify /etc/pam.d/common-session and insert the following line.
session  required                        pam_limits.so
  This is a "feature" unique to Debian based distros.  Now with all of that done, MusE will come up with, yes, you guessed it, another window complaining about timing.  It wants at least 1024.  So, the last thing you have to do is enable permissions on /dev/rtc0 (and possibly /dev/rtc as well), and raise the max user frequency.
su
echo 2048 > /sys/class/rtc/rtc0/max_user_freq
chmod 777 /dev/rtc0
  That should get everything up and running.  You may want to put that into a boot script, but I haven't been able to get it working reliably yet.  I might do an update if/when I get it working.

No comments:

Post a Comment