Configuring PulseAudio with Jack Audio Connection Kit running via DBus is pretty easy nowadays. Following procedure was tested on Gentoo Linux but it should probably apply to other Linux distributions too. Used versions of packages were
media-sound/jack-audio-connection-kit-2.9999 (from pro-audio overlay).
First you should check the name of the sound card you want Jack to play sound via. Use command
aplay -l to get the name of the sound card. Then run following command to set the card for Jack:
jack_control dps device hw:DX
DX with the name of your sound card.
Second, we’ll make sure Jack will use Alsa for output. Following command will set Jack output to Alsa:
jack_control ds alsa
If this command fails, make sure you have Python 2.7 selected as the active Python version.
jack_control does not work with Python 3.2 because new Python changed
Last step is to start Jack and optionally configure PulseAudio. Issue the following command:
pulseaudio -k && jack_control start && pacmd set-default-sink jack_out && pacmd set-default-source jack_in
This command line first kills PulseAudio, then it starts Jack and tells PulseAudio to use Jack by default both for input and output.
If you do not get sound from sound applications that play sound via PulseAudio, use
pavucontrol to check that the sound output for given application is directed to Jack sink.