Have you tried “killall jack” as that should kill any processes called jack which are running.
Or “ps -ef | grep jack” should highlight any processing running with jack in their name. Ignore teh one that ends “grep --color=auto jack” as that is the process you just ran to highlight jack itself.
I just recognized that when I start Renoise, jackd is started automatically. This is the normal way?
When you installed the RT kernel, did you use startup manager to change the boot process to use the RT kernel? Installing from synaptic alone won’t necessarily make the new kernel boot.
are you trying to run a renoise 32bit on a 64bit system, by any chance ? It would explain the segmentation fault.
I am not sure how good the rt kernels for mint are, every distro is different. But you def want a rt kernel for audio work in linux. Do you have qjackctl installed? that is what you want to use to control jack.
When setting up any distro these are the steps I take.
Install the distro
install rt kernel
Install ATI or Nvidia drivers if needed
reboot
create audio group
set the limits.conf
enable alsa midi-seq
reboot
install jack, qjackctl, ardour, sweep, ams
install renoise
build and tweek system
when i want to work with audio
start qjackctl (you need to play around with the settings - make sure rt is checked)
then renoise
I am running i686 which supposed to be 32bit, isnt it?!
Ofc I tweaked the bootupmanager to load the new kernel on startup, checked it twice with systemprofiler, to be sure I am running the rt kernel. 
qjackctl is installed along with jackd. Audio group already exists. And definetly works, since I now can use rt priority with jack+renoise without having a rt kernel installed.
The strange thing about it is, I only have to start Renoise and “Renoise makes jack start automatically in the backround(without GUI)”!
I never had this “issue”, its working normal as i am used to. But I like to start jack, make it work and start renoise after. 
btw, i am not using any hardware I think i dont really need ultra low latencys due to realtime kernel, ~30ms are fine for me.
Hi,
The mystery deepens! But I guess as long as its working fine for you, that’s great. What version of Jack are you running? You should be able to type jackd --version without getting an error message. I’m using 0.118 wihtout any problems. I have written a blog about setting up linux mint 8 to use jack with a realtime kernel, it’s at www.tuxaudio.blogspot.com
“jackd version 0.116.1 tmpdir /dev/shm protocol 24” is installed via apt-get.
I will check your blog out. The problem is, i cannot change the settings of jack when its started in the backround by renoise.
You can start jack before Renoise does by using jackctl, then you can change lots of stuff in Jack.
I did this ofc. And I said, when I press “Start”, I end up with an error message like this:
I just reinstalled Mint Linux 8 Helena from the scratch with this roadmap
.
Nothing changed. Still this error.
Hmmm… the only thing I can think of… some other program or process is hogging your sound card. On my system the laptop’s built-in sound card can be used for regular audio stuff, and my external USB interfaces is dedicated to using jack. Try switching off the sound in gnome’s control center, and then starting jack. Also ensure any app that can access sound is closed (e.g. your web browser).
Is your user in the audio group?
sudo adduser audio
or
su root
adduser audio
exit
I have spare space, I will install Mint and document my steps…
Try “- nice -10” instead of “-nice -10”.
I get a similar error to above if I have something like a media player open that is using Pulse Audio or ALSA and thus Jack wont connect to the sound card. Does it work if you try and launch Jack (qjackcatl) before anything else after booting?
I do still always get a “Connection failure: Connection refused” message on qjackctl but it has never stopped it operating as expected so not sure what that is about.
Are Jackd and the Jack client both the same version? the client won’t connect if there is a difference.
It connects and works, I have used it in Renoise and VLC (although I have to remake the connection for VLC every time it loads a new file which is a bit of a pain) so fairly sure it’s work. Think it’s related to PA more than Jack.
Not in a state to play around right now as listening to classical and opera (bit different for me. Recommendations please 
) on Youtube and to start Jack I need to close Firefox if it’s had media or flash playing and also close reopen to get audio working from it again after stopping Jack and too hungover (and not enjoying work but at least it’s quite) to be bothered with all that right now.
I’m pretty sure I get that message twice in Terminal when I run qjackctl but if I run it with a sudo command I only get it once. Don’t generally bother with sudo for Jack or Renoise although some people have recommended doing so…
It’s possible to use a Pulseaudio-Jack module so everything gets rerouted via jack. I’ve got my system set up to do that. It’s always handy to be able to watch, say, a tutorial video, and work along in renoise 
To get pulseaudio and jack to talk to each other you need at least jack 0.118 and PA 0.9.21, plus the pulseaudio-jack module. Once you get over that hurdle its relatively straightforward to get it running.
Is there a way to tell synaptic or apt-get to install 0.118 jack instead of my 0.116?
Yes there is. You have to add a repo… ppa:motin/until-jack-is-included-in-main
sudo add-apt-repository ppa:motin/until-jack-is-included-in-main
sudo apt-get update
Why do I still see version 0.166 of jackd in synaptic package manager?
So I decided to download the source —> sudo sh configure
brings me a warning that jack is installed. (after a clean os installation?)
Check /usr/lib and found libjackblablabla…synaptic tells me that it belong somehow to gstreamer-bad. And Dependencies Information told me that it conflicts with jack. Guess here is the overall problem!!!
Anyway, how the **** can I tell synaptic to use ppa repository in that way I can install 0.188 version of jackd??? Do I need to deactivate the normal repo which is including jackd 0.166???