[SOLVED] jack2dbus is running but I can't seem to use Qtractor/Ardour

Question

Hello,
Earlier I had alsa installed together with jack2 and both worked fine - I could record my songs in Qtractor without any problems.
But I reecently bought GuitarPro software for Linux which needs a pulseaudio to work. So I installed the pulseaudio and It is
working fine by itself. I can start/stop it using commands:
pulseaudio --start
pulseaudio --kill
Now the problems begin. I had to uninstall jack2 and swap it for jack2dbus which works with pulseaudio (jack2 doesn't).  I allso
wrote two scripts for starting the jack2dbus in two separate configurations
Hardware default audio (Nvidia) for playback and USB audio interface (Scarlet 2i4) for recording:
#!/bin/bash
jack_control start
jack_control eps realtime true
jack_control ds alsa
jack_control dps period 265
jack_control dps playback hw:0,0
jack_control dps capture hw:USB
USB audio interface (Scarlet 2i4) for playback and recording.
#!/bin/bash
jack_control start
jack_control eps realtime true
jack_control ds alsa
jack_control dps device hw:USB
jack_control dps period 265
THE START PROCEDURE
I first start the pulseaudio and check if it is running.
$ pulseaudio --start
$ ps aux | grep pulse
ziga 4171 48.0 0.2 520004 15328 ? S<l 14:22 0:00 pulseaudio --start
ziga 4176 0.0 0.0 76628 2552 ? S 14:22 0:00 /usr/lib/pulse/gconf-helper
ziga 4179 0.0 0.0 10820 1076 pts/2 S+ 14:22 0:00 grep pulse
then I start the jack server using one of the scripts above and check if jack is running.
$ jack_control status
--- status
started
At this instance when everything seems to be running when I start Qtractor or Ardour I allways get the error.
The audio/MIDI engine could not be started! In the image check allso the console in the background.
I get some prompt about pulseaudio "module-jackdbus-detect" when I 1st shutdown jack, then kill pulseaudio
and restarting it using different command than before. Could this be the clue to what is wrong? Please help a bit.
$ jack_control stop
--- stop
$ pulseaudio --kill
$ pulseaudio
W: [pulseaudio] pid.c: Stale PID file, overwriting.
E: [pulseaudio] module-jackdbus-detect.c: Failed to parse channels= argument.
E: [pulseaudio] module.c: Failed to load module "module-jackdbus-detect" (argument: ""): initialization failed.
E: [pulseaudio] main.c: Module load failed.
E: [pulseaudio] bluez5-util.c: GetManagedObjects() failed: org.freedesktop.DBus.Error.ServiceUnknown: The name org.bluez was not provided by any .service files
Last edited by 71GA (2014-05-18 10:16:47)

Answer 1

ooo wrote:
Quite impossible to guess what the issue could be from that error.
I suggest trying if you can get jack working using the legacy jackd. Even if that won't work you may get more useful error message.
Btw, if you install the jack2 package it includes both jackdbus and jackd, so it should be ok in your case, unless you absolutely want to get rid of the old jackd.
OK thank you for the sugestion. I did uninstall jack2-dbus and installed jack2 together with a python2-dbus dependancy. Then I killed pulseaudio and tried to start jack server.
It was unsucessfull but as you said I did get some more feedback. I saw that priority is only 10. IS it possible this is too low? Where can I set this parameter?
$ ps aux | grep pulse
ziga 5171 0.0 0.0 10820 1076 pts/1 S+ 21:12 0:00 grep pulse
$ jackd -R -dalsa -dhw:USB -p256
jackdmp 1.9.9.5
Copyright 2001-2005 Paul Davis and others.
Copyright 2004-2012 Grame.
jackdmp comes with ABSOLUTELY NO WARRANTY
This is free software, and you are welcome to redistribute it
under certain conditions; see the file COPYING for details
no message buffer overruns
no message buffer overruns
no message buffer overruns
JACK server starting in realtime mode with priority 10
audio_reservation_init
Failed to acquire device name : Audio2 error : Device reservation request with priority 2147483647 denied for "Audio2" via RequestRelease()
Audio device hw:USB cannot be acquired...
Cannot initialize driver
JackServer::Open failed with -1
Failed to open server
Last edited by 71GA (2014-05-12 19:17:10)