On Sun, May 16, 2010 at 7:12 PM, Fernando Lopez-Lezcano <nando@ccrma.stanford.edu> wrote:
> > a potential bad interaction between pulseaudio and jack (through
> > /etc/security/limits.conf, potential priority escalation issue).
...
Not that many "tweaks". The ability for all users to run jack with
realtime scheduling is "added" when you install the Planet CCRMA jack
package. That thread talks about some security problems that could arise
with the use of realtime scheduling, that is definitely not the source
of your problems.
HOWEVER -- in testing out a new $5.00 soundcard, I also experienced transient lock-ups again with jackd/qjackctl. The one thing that I could point to consistently as causing problems: having the wrong settings in 'alsamixer', i.e. when one of these is set to "on" you can neither play directly through ALSA, and jackd will hang:
** in alsamixer (F3-playback):
Item: "Multi Track Rate Locking" set to [Off]
Item: "Multi Track Rate Reset" set to [Off]
Likewise, if the card is locked to the wrong sampling rate , jack may not be able to reset it if the above settings are wrong.... To make things worse, it seems like some of these settings are "sticky" and may require loading/unloading the driver module or rebooting for the change to take effect.
-- Niels