Ardour NOT Launcing

So what on earth is wrong with my system ?

Both Ardour v5.12 x64 and Mixbus v3.7 fail to open on Ubuntu Studio 18.04 …

I mean I can get to the start audio dialogue, but after that …

… nothing happens ;
no matter if I choose ALSA or Jack as sound system .

If I start QJackCtl before starting Ardour or Mixbus … they say Jack is already running and after that I’m faced with a system crash pop-up . argh !!!

Tried two audio interfaces ;
A Zoom G2nu and a Line 6 Pod Studio GX, both are detected by QJackCtl as well as Ardour and Mixbus .

Some help around here …

Strange as it seems ;
REAPER x64 - Linux Native (x64) v5.941 seems to work with both of the tested interface .
The click-sound is playing back steadily and there’s no hick-up / crackling or anything like that .

I uninstalled csladspa, but have yet to try again ;
for it seems my PreSonus FIRESTUDIO project is not working (constant red connection light) …
So no connection .

Any info about that one ?

general troubleshooting tip: start a GUI program from a terminal window, often the program will display additional messages in the terminal to indicate problems.
general forum tip: If you aren’t going to check out the suggested solution to your original problem, wait until you have time to do that, don’t post some unrelated question into the same forum topic, it makes searching difficult for others who seek information on the same or similar problem as your original question.

I highly recommend to use a different, dedicated pro-audio system e.g. AVLinux or KXStudio. AVLinux can also run live from USB-key or DVD and is handy for a 2nd opinion.

This is most likely due to a plugin that was packaged untested. Ubuntu and it’s derivatives incl. UbuntuStudio are notorious for repeatedly causing issues. Perhaps related to – To know for sure what causes the issue, we will need a backtrace: