The JACK sound server needs to be running in order to run IDJC. In order to manually start it try something like: $ jackd -d alsa -r 44100 -p 2048 If you would like JACK to start automatically when you start IDJC try this: echo "/usr/bin/jackd -d alsa -r 44100" >~/.jackdrc If you have already done this it is possible another application or non-JACK sound server is using the sound card. Possible remedies would be to close the other audio app or configure the sound server to go into suspend mode after a brief amount of idle time. ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// neyder@Candelaria:~$ jackd -d alsa -r 44100 -p 2048 jackd 0.102.20 Copyright 2001-2005 Paul Davis and others. jackd comes with ABSOLUTELY NO WARRANTY This is free software, and you are welcome to redistribute it under certain conditions; see the file COPYING for details JACK compiled with System V SHM support. loading driver .. apparent rate = 44100 creating alsa driver ... hw:0|hw:0|2048|2|44100|0|0|nomon|swmeter|-|32bit control device hw:0 the playback device "hw:0" is already in use. Please stop the application using it and run JACK again cannot load driver module alsa no message buffer overruns