system/alsa_pcm not under connections in QJackCtl

[devourer09]

I am trying to get Jack to play sound out of my speakers. The server will start up but I don't hear any sound. The problem I had before this was that the server wouldn't start because I didn't install the pulseaudio-module-jack. After I installed that the server started fine but no sound comes out. I believe it is because I don't have a system or alsa_pcm showing up under QJackCtl's connections window. Here is a screenshot:

Also, when I do:

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lsof +c 0 /dev/snd/pcm*

I get this:

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COMMAND     PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
pulseaudio 1710 devo  mem    CHR  116,6          8447 /dev/snd/pcmC0D0c
pulseaudio 1710 devo   54u   CHR  116,6      0t0 8447 /dev/snd/pcmC0D0c

I'm not sure if that means pulseaudio is hogging the ALSA driver or not... because the Jack server will start.

In the PulseAudio system settings I can switch the output to Analog Output and sound will come out but when I switch to the PulseAudio Jack sink nothing comes out. Here's a screenshot:


BTW, I'm on Ubuntu 12.04 and I'm just trying to get sound to work. I'm not worried about midi or anything. I'm just an amateur who wants to mess around with making music and noise. I'll be happy to post any other information from the terminal and what not.

Thanks.

[Pablo]

What are the terminal outputs of:

cat ~/.jackdrc
(or a screenshot of qjackctl's setup, configuration tab)

and

arecord -l && aplay -l

?

[devourer09]

Ok. I've now disabled PulseAudio so I can just focus on Jackd and make sure PA is not blocking Jackd from accessing my sound card. Now when I try to start jackd it fails. Here is the output of QJackCtl's message window:

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12:53:56.123 Patchbay deactivated.
12:53:56.170 Statistics reset.
12:53:57.820 ALSA connection change.
12:53:59.993 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 socket
jack server is not running or cannot be started
12:54:08.117 D-BUS: JACK server could not be started. Sorry
Mon Nov  5 12:54:07 2012: Starting jack server...
Mon Nov  5 12:54:07 2012: JACK server starting in realtime mode with priority 10
Mon Nov  5 12:54:07 2012: control device hw:0
Mon Nov  5 12:54:07 2012: control device hw:0
Mon Nov  5 12:54:07 2012: Acquired audio card Audio0
Mon Nov  5 12:54:07 2012: creating alsa driver ... hw:0|hw:0|1024|3|44100|0|0|nomon|swmeter|-|32bit
Mon Nov  5 12:54:07 2012: control device hw:0
Cannot connect to server socket err = No such file or directory
Cannot connect to server socket
jack server is not running or cannot be started
Mon Nov  5 12:54:08 2012: [1m[31mERROR: 
ATTENTION: The playback device "hw:0" is already in use. The following applications  are using your soundcard(s) so you should  check them and stop them as necessary before  trying to start JACK again:
chrome (process ID 2616)
[0m
Mon Nov  5 12:54:08 2012: [1m[31mERROR: Cannot initialize driver[0m
Mon Nov  5 12:54:08 2012: [1m[31mERROR: JackServer::Open() failed with -1[0m
Mon Nov  5 12:54:08 2012: [1m[31mERROR: Failed to open server[0m
Mon Nov  5 12:54:08 2012: Saving settings to "/home/devo/.config/jack/conf.xml" ...
12:54:12.651 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 socket
jack server is not running or cannot be started

Apparently Chrome is blocking Jack... I just noticed that. Let me test starting the server without Chrome open and see if that works. I'll update this post with my results.
Edit: Ok, I shut down Chrome and tried again and I got the same message as before minus the line telling me that Chrome is using my sound card.

Something must be wrong in your jack setup.
It seems that jack is not even running... ?

Try setting the input/output ports to match what you have (like 2 inputs, 2 outputs), and restart JACK.
You can also try to use the 'dummy' backend, just to make sure JACK is operating properly.

Before I disabled PA jackd was starting. And how do I determine how many ports I have?

What are the terminal outputs of:

cat ~/.jackdrc
(or a screenshot of qjackctl's setup, configuration tab)

and

arecord -l && aplay -l

?

Here is a screenshot of QJackCtl's setup window:


arecord -l && aplay -l give this:

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**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC888 Analog [ALC888 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 1: ALC888 Digital [ALC888 Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 2: ALC888 Analog [ALC888 Analog]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC888 Analog [ALC888 Analog]
  Subdevices: 0/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 1: ALC888 Digital [ALC888 Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

[devourer09]

I guess it's up to me to look through Jack's source and see what is causing this specific error.

Ok. I've found the source file where I get the error

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Cannot connect to server socket err =

Here is a link to the file in Jack's github repository: https://github.com/jackaudio/jack2/blob ... Socket.cpp

[Pablo]

Sorry, I missed your post. I am not sure what happens but try this:

Find out what processes are using your soundcard:

lsof /dev/snd/*

and kill'em all.

You might need to avoid pulseaudio autospawn. I am not sure if this will make any difference but you can try. So, create the file:

~/.pulse/client.conf

and type there:

autospawn=no

Also, try disabling "interface via D-Bus" in "Others" tab.

Instead of or in adition to looking through jack source, you can try to contact the jack developers, possibly via IRC, #jack channel at freenode.net. Or the qjackctl developer via the forum at rncbc.org.