Hey,
I recently re-installed ubuntu 12.04 and did this tutorial installing the audiopackages including qjackctl. For some reason qjackctl won't work, and since I'm quite the newbie at this, I have no idea why.
This error code is produced:

Code:
20:02:26.955 Patchbay deactivated.
20:02:26.960 Statistics reset.
20:02:26.965 ALSA connection change.
20:02:26.977 D-BUS: Service is available (org.jackaudio.service aka jackdbus).
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
20:03:25.593 D-BUS: JACK server could not be started. Sorry
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
Fri Jan 11 20:03:25 2013: Starting jack server...
Fri Jan 11 20:03:25 2013: JACK server starting in realtime mode with priority 10
Fri Jan 11 20:03:25 2013: ERROR: cannot register object path "/org/freedesktop/ReserveDevice1/Audio0": A handler is already registered for /org/freedesktop/ReserveDevice1/Audio0
Fri Jan 11 20:03:25 2013: ERROR: Failed to acquire device name : Audio0 error : A handler is already registered for /org/freedesktop/ReserveDevice1/Audio0
Fri Jan 11 20:03:25 2013: ERROR: Audio device hw:0 cannot be acquired...
Fri Jan 11 20:03:25 2013: ERROR: Cannot initialize driver
Fri Jan 11 20:03:25 2013: ERROR: JackServer::Open failed with -1
Fri Jan 11 20:03:25 2013: ERROR: Failed to open server
Fri Jan 11 20:03:26 2013: Saving settings to "/home/bixop/.config/jack/conf.xml" ...
20:03:28.230 Could not connect to JACK server as client. - Overall operation failed. - Unable to connect to server. Please check the messages window for more info.
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
these are screens of my settings in qjackctl.
Screenshot from 2013-01-11 20:35:50.png

Screenshot from 2013-01-11 20:35:55.png


Very thankful for any help!