[PlanetCCRMA] cannot get jack & alsa running as non-root user

Fernando Lopez-Lezcano nando@ccrma.Stanford.EDU
Mon Feb 14 11:00:01 2005


On Sun, 2005-02-13 at 16:37, francisco echeverria wrote:
> Hi  all
> 
> first of all thanks to chaos for the answer of my previous post... it 
> was a really dumb question...:P
> 
> Now my actual problem:
> 
> i've upgraded my fc1 ccrma partition to fc2 not without problems, but 
> now everything appears to work fine for me (fc2 not ccrma), except that 
> i cannot run qjackctl as a normal user. My upgrade process consist on 
> uninstalling all extra packages  (ccrma and others), then upgrade to fc2 
> via yum, and finally getting ccrma fc2 packages and updates.
> 
> first: it gets me into an error telling me that he could not open ALSA 
> sequencer as client and so there's no midi patchbay available.
>    
>     20:51:59.149 Patchbay deactivated.
>     20:51:59.596 Statistics reset.
>     20:51:59.601 Could not open ALSA sequencer as a client. MIDI 
> patchbay will be not available.
>     ALSA lib seq_hw.c:446:(snd_seq_hw_open) open /dev/snd/seq failed: 
> Acces denied

This can be solved by enabling the alsasound startup script:
  /sbin/chkconfig alsasound on
Next reboot or restart of alsasound will load snd-seq.

> second: when i try starting  jackd using alsa driver (oss and dummy 
> aparently workingbut without midi patchbay) i get this:
> 
>     21:07:16.285 Startup script...
>     21:07:16.285 artsshell -q terminate
>     21:07:16.621 Startup script terminated with exit status=256.
>     21:07:16.622 JACK is starting...
>     21:07:16.622 /usr/bin/jackd -R -dalsa -dhw:0 -r44100 -p1024 -n2 -S
>     21:07:16.640 JACK was started with PID=10504 (0x2908).
>     jackd 0.99.36
>     Copyright 2001-2003 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|1024|2|44100|0|0|nomon|swmeter|-|16bit
>     ALSA: Cannot open PCM device alsa_pcm for playback. Falling back to 
> capture-only mode
>     cannot load driver module alsa
>     21:07:16.781 JACK was stopped successfully.
>     21:07:18.669 Could not connect to JACK server as client.

It looks like it can't open the alsa playback channel. Maybe some other
application is using sound? Check for the gnome and/or kde sound servers
(depending on which desktop you use). 

Something to test, can another alsa application run? For example, use
alsaplayer to play some soundfile. If it does not run most probably some
program or process is using the sound device. 

If the sound device is free try start jack with different parameters,
for example buffer size < 1024 and/or number of periods > 2. 

-- Fernando