FC13/KDE

I having problems with jackd not starting, because it can't find a backend

Which one do I use pulseaudio or alsa ?

There is no output in /var/log/messages for jackd.

Here is the output of running "jackd"

$ jackd
jackd 0.118.0
Copyright 2001-2009 Paul Davis, Stephane Letz, Jack O'Quinn, Torben Hohn 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

jackd 0.118.0
Copyright 2001-2009 Paul Davis, Stephane Letz, Jack O'Quinn, Torben Hohn 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


usage: jackd [ --no-realtime OR -r ]
             [ --realtime OR -R [ --realtime-priority OR -P priority ] ]
      (the two previous arguments are mutually exclusive. The default is --realtime)
             [ --name OR -n server-name ]
             [ --no-mlock OR -m ]
             [ --unlock OR -u ]
             [ --timeout OR -t client-timeout-in-msecs ]
             [ --port-max OR -p maximum-number-of-ports]
             [ --debug-timer OR -D ]
             [ --no-sanity-checks OR -N ]
             [ --verbose OR -v ]
             [ --clocksource OR -c [ c(ycle) | h(pet) | s(ystem) ]
             [ --replace-registry ]
             [ --silent OR -s ]
             [ --version OR -V ]
             [ --nozombies OR -Z ]
      

  -d backend [ ... backend args ... ]
             Available backends may include: alsa, dummy, freebob, firewire, net, oss, sun, or portaudio.

       jackd -d backend --help
             to display options for each backend


[mickey@Acer ~]$ jackd -d backend --help
jackd 0.118.0
Copyright 2001-2009 Paul Davis, Stephane Letz, Jack O'Quinn, Torben Hohn 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

jackd: unknown driver 'backend'




# jackd -d pulseaudio
jackd 0.118.0
Copyright 2001-2009 Paul Davis, Stephane Letz, Jack O'Quinn, Torben Hohn 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

jackd: unknown driver 'pulseaudio'




[root@Acer mickey]# jackd -d alsa
jackd 0.118.0
Copyright 2001-2009 Paul Davis, Stephane Letz, Jack O'Quinn, Torben Hohn 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 ..
creating alsa driver ... hw:0|hw:0|1024|2|48000|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




There are no other applications using the sound system.