> I played with it, but couldn't make it start jackdbus. The advanced
> dialog has a "Server prefix"/Server path (command line prefix) where it
> currently says "jackd". It's a list that also contains "jackdmp" and
> "jackstart" none of which works (I get an error "could not start jack,
> sorry"). I tried typing "jackdbus" here which also didn't work, with the
> error "Could not connect to the jack server as client".
>


Settings > Misc > Enable D-Bus Interface.

Not my screenshot, found through Googling. Strangely the screenshot on the official page for the Misc options doesn't have it and seems rather old/lacking....

http://alien.slackbook.org/blog/wp-content/uploads/2014/01/qjackctl_setup_misc.png