[LAU] jitsi via jackd

[Peter P.]

* Peter P. <peterparker at fastmail.com> [2020-04-09 03:54]:
> * david <gnome at hawaii.rr.com> [2020-04-09 03:35]:
> > On 4/8/20 3:20 PM, Peter P. wrote:
> > > Hi list,
> > > 
> > > I am happily using Jitsi for various tasks since a few weeks and would
> > > like to run its application image
> > > https://github.com/jitsi/jitsi-meet-electron/releases/
> > > over jackd.

[...]

> It turns out a few minutes ago that they just introduced a fatal bug for
> their AppImage https://github.com/jitsi/jitsi-meet-electron/issues/244
> which might affect you as well.
And which can be circumvented by starting the applicatino image with the
--no-sandbox flag by the way.

But back to using jack for alsa-only applications. Following the guide
on https://jackaudio.org/faq/routing_alsa.html I installed the
libasound2-plugins Debian package, which includes the jack pcm plugin
for alsa. This plugin is activated by
/usr/share/alsa/alsa.conf.d/50-jack.conf as a hardware plugin without
conversions, meaning that it is tied to jack's sample rate and bit
resolution. I was able to create a "plug" device which takes care of
this conversion in an ~/.asoundrc yielding
	
 pcm.jackconv{
	type plug
	slave { pcm "jack" }
	hint {description "jack plugin with software conversions" }

aplay -L then lists this device. My next question is, how can I tell
applications to use this device? I want to avoid declaring it the
default in .asoundrc with an 
 pcm.!default{
	type plug
	slave { pcm "jack" }
	hint {description "default jack plugin with software conversions" }

I found out that there is an environment variable ALSA_PCM_CARD= but
this can only set hardware devices but not pcm device names such as my
jackconv. Then I discovered ALSA_PCM_DEVICE and tried to start jitsi
with
 ALSA_PCM_DEVICE=jackconv ~/bin/jitsi-meet-2.0.0-x86_64.AppImage
but no device "jackconv" shows up in jitsi nor are any jack ports
created for it.

Is there something I am doing wrong?
Thanks for all ideas!
cheers, P