jackd won't start in X

[tomdeb <tom@tomdeb.org>]

Hello,

I am trying to migrate away from pulseaudio and currently testing out
jack-audio-connection-kit 

For some unknown weird reason jackd won't start if I launch it via an
X terminal. I get the following: 

~ > /usr/bin/jackd -R -dalsa -r48000 -p1024                                 

JACK is running in realtime mode, but you are not allowed to use
realtime scheduling.
Please check your /etc/security/limits.conf for the following lines
and correct/add them:

  @audio          -       rtprio          100
  @audio          -       nice            -10

After applying these changes, please re-login in order for them to
take effect.

You don't appear to have a sane system configuration. It is very
likely that you
encounter xruns. Please apply all the above mentioned changes and
start jack again!
[1]    8509 exit 255   /usr/bin/jackd -R -dalsa -r48000 -p1024

These settings are set correctly in /etc/security/limits.d/audio.conf
and I am member of the audio group.

But it works if I start it on tty1 or if I ssh@localhost.

Any clue/help will be much appreciated.

Tom