[xubuntu-users] qjackctl crashes

[Andrew Bryant]

I've just installed Xubuntu 10.4, and added jackd (with which comes 
qjackctl)

Starting qjackctl looks OK

Clicking on the green triangle appears to run jackd, but qjackctl 
freezes: none of the buttons works, and if I wipe a window across 
qjackctl's gui, the gui remains blank.

In the messages window I get:

<
Memory locking is unlimited - this is dangerous.  You should probably 
alter the line
   @audio - memlock unlimited
in /etc/limits.conf
etc
 >

This puzzles me.  For a start, there is no /etc/limits.conf - the file 
is /etc/security/limits.conf.  I suppose this is a typo in the error 
message.

BUT, when I do edit the line in /etc/security/limits.conf, the warning 
continues to appear.  (And it also appears if I add a link i 
/etc/limits.conf pointing to /etc/security/limits.conf.

Furthermore, in

https://help.ubuntu.com/community/Ubuntu%20Studio%20Upgrade%20from%20Ubuntu

is a warning against editing this file by hand.  This page refers to a 
file written by jackd - /etc/security/limits.d/audio.conf, which does 
not exist.

I am trying to use this system in 512MB of memory.  Is this over-ambitious?

Andrew.