JACK (permissions?) problem, "Connection refused"; only SuperCollider can make sound

What other apps and distros do you use to round out your studio?

Moderators: khz, MattKingUSA

Jeff Brown
Established Member
Posts: 33
Joined: Sun May 21, 2017 2:11 am

JACK (permissions?) problem, "Connection refused"; only SuperCollider can make sound

Postby Jeff Brown » Tue Mar 27, 2018 4:11 pm

Everything was working until my computer crashed Monday. Now only SuperCollider can make sound.

I'm using KXStudio. Cadence starts automatically at login. It used to start JACK automatically, but now it doesn't. I can start JACK (according to Cadence) either from Cadence itself, or by booting the server in SuperCollider. Whenever I start JACK I get a popup notice, "Automatic studio created: JACK server is started not by ladish daemon and there is no loaded studio, so a new studio is created and marked as started."

With JACK running, I can use SuperCollider as normal, but no other apps. It used to be that with JACK running I would see it in the KDE toolbar, but now that's not true.

If I open a Youtube video in Chrome, I get video but no sound. If I play a SoundCloud clip, the view advances as if playing but no sound. In Firefox, SoundCloud won't even start; I only get a circular icon that spins forever as if it's about to start. In VLC, if I open an mp3 file, I get

Audio output failed:
The audio device "default" could not be used:
Connection refused.


With JACK not running, if I "force restart" in Cadence, I get a a popup report that ladish daemon has been deactivated. With JACK running, if I "force restart" in Cadence, I get popup reports that ladish daemon and jackdbus both crashed.

I've rebooted a lot.

User avatar
thetotalchaos
Established Member
Posts: 151
Joined: Mon Sep 29, 2014 8:29 pm
Contact:

Re: JACK (permissions?) problem, "Connection refused"; only SuperCollider can make sound

Postby thetotalchaos » Tue Mar 27, 2018 7:24 pm

Check if your "default" audio device is indeed your soundcard, and not for example ALSA loopback device.
What exactly was this "crash on monday"? What happened exactly?
Maybe some of this could help you: https://www.linuxmusicians.com/viewtopic.php?f=27&t=17780&hilit=cadence+tips#p87243

IMHO Cadence is still in Beta state and not quite ready to inherit Qjackctl. It can be hit and miss experience sometimes. And its still too dependent of external settings, thus not providing the expected out-of-the-box experience. This is a real issue for the new users.
Check out my latest music album The girl with the stars in her eyes
https://totalchaos-music.bandcamp.com/album/the-girl-with-the-stars-in-her-eyes

Jeff Brown
Established Member
Posts: 33
Joined: Sun May 21, 2017 2:11 am

Re: JACK (permissions?) problem, "Connection refused"; only SuperCollider can make sound

Postby Jeff Brown » Tue Mar 27, 2018 8:05 pm

How do you check what the default audio device refers to? More generally, how do you investigate what's going on? I feel guilty whenever I have an audio problem because while I know how to experiment, I don't know how to investigate. I just try stuff at random and record what I've done and try to cover the whole space of possibilities without repeating my footsteps, and if that takes more than a couple hours I ask what often ends up having been a dumb question.

This question turns out to have been one of those dumb questions. But on the bright side, I solved the audio problem!


The crash

During the crash, which sort of thing happens to me something like twice a week, I was using maybe seven applications (Chrome, Dolphin, Konsole, Emacs, Cadence, Keybase and gnome-encfs-manager, plus things that KDE starts without asking me like KOrganizer and KDE connect) with maybe fifteen tabs open in Chrome. My keyboard stopped working. My mouse would move, but I couldn't use the keyboard command to turn it into a skull and kill the app under it. Couldn't switch apps. The fan started to go fast. I tried to get control for a while, then did a hard reset.

I don't remember if I did this Monday, but often I'll try to switch to a different (workspace? login session?) with Ctrl-Alt-Fx (for x in [1,6], 7 being the default one), and it usually works but it's so slow that I've never carried through to the end-goal of killing processes in the original workspace.

The audio problem: Solved

I just had to start PulseAudio from within Cadence. Sorry for bothering you when the answer was so easy. I've never had to do that before.

User avatar
thetotalchaos
Established Member
Posts: 151
Joined: Mon Sep 29, 2014 8:29 pm
Contact:

Re: JACK (permissions?) problem, "Connection refused"; only SuperCollider can make sound

Postby thetotalchaos » Tue Mar 27, 2018 8:34 pm

The easiest way to check what is your default audio device is to open Qjackctl or Cadence and look which is your HW:0,0 device. You can arrange the order by making a short script in /etc/alsa-base.conf like i did in my example above. Here is a nice manual on the topic from Archlinux wiki: https://wiki.archlinux.org/index.php/Advanced_Linux_Sound_Architecture#Set_the_default_sound_card
Check out my latest music album The girl with the stars in her eyes
https://totalchaos-music.bandcamp.com/album/the-girl-with-the-stars-in-her-eyes


Return to “Linux Distributions & Other Software”

Who is online

Users browsing this forum: No registered users and 2 guests