"JACK server could not be started" when using Qjackctl

None of these solved my problem. This did: http://dpod.kakelbont.ca/2015/08/16/fixing-qjackctl

1. In a terminal start qjackctl:

   qjackctl
   

2. Before you try to start it, click the Setup button in the GUI (right-hand side, middle).

   

3. On the setup GUI change Input Device and Output Device (middle, right-hand side) from (default) to hw:PCH (In the screenshot one has been changed and the other has not).

   

4. Restart qJackCtl. You should now be able to successfully use the Start button.

Try this from the command line:

pulseaudio --kill  
jack_control  start

Then when your done do this:

jack_control exit  
pulseaudio --start

And sometimes jack wont die, so then do

Get jackd's PID:

ps -aux | grep jackd  
kill -9 jacksPID

I made it and solved:

sudo killall -9 jackdbus