[LAU] jack/firewire block apps from using buildin soundcard

[Ng Oon-Ee]

On Tue, 2009-12-15 at 10:16 +0100, Atte André Jensen wrote:
> Ng Oon-Ee wrote:
> 
> > When qjackctl opens, jack is usually started (AFAIK). 
> 
> Not necessarily...
> 
>  > Pulseaudio, for
> > better integration with JACK, gives up control of the soundcard to JACK
> > whenever JACK starts. This is not an error, its by design. The idea is,
> > if you're using JACK, you want it to have the soundcard, not pulse.
> > 
> > AFAIK, however, pulse only gives up a soundcard if jack takes it. This
> > should not happen if qjackctl doesn't start jack (I believe it does
> > start jack though).
> 
> First: I setup qjackctl to *not* start jack, and indeed it isn't, at 
> least jack clients started up with qjackctl open, but jack not started, 
> complains that jack is not running.
> 
> Second: Firefox (let's take that as an example) uses the buildin 
> soundcard, and qjackctl/jack is using the firewire card.
> 
> If jack is running I'm of course not expecting non-jack apps to be able 
> to access the soundcard that jack is using, but this is not the case here...
> 
You may want to check what qjackctl does in Ubuntu then. The script may
be calling pasuspender, for example. The behaviour I was talking about
is consistent with my experience with latest jack2/pulseaudio in Arch
Linux, and indeed with intended behaviour (by the dev).

The other thing I just realized, if you're using jack1 instead of jack2
in Ubuntu the above behaviour would not apply (no dbus in jack1), so
pasuspender may be used as a 'workaround'.