vilytwisted@evilytwisted-desktop ~ $ ps aux | grep jack
1000      3094  0.0  0.0      0     0 ?        Z    21:30   0:00 [jack_lsp] <defunct>
1000      3431  0.1  0.1 168992 10932 ?        Ssl  21:44   0:00 /usr/bin/jackdbus auto
1000      3645  0.0  0.0   4396   612 ?        S    21:50   0:00 /bin/sh /usr/bin/qjackctl
1000      3651  1.7  0.5 731712 48592 ?        Sl   21:50   0:03 /usr/lib/qjackctl/qjackctl.real
1000      3703  0.0  0.0  13584   888 pts/0    S+   21:54   0:00 grep --colour=auto jack
evilytwisted@evilytwisted-desktop ~ $ sudo killall -9 jack
jack: no process found
evilytwisted@evilytwisted-desktop ~ $