[Alsa-user] alsa-only applications (such as jitsi) via jackd

[Peter P. <pet...@fa...>]

Dear Alsa-list,

I had asked this on the Linux-Audio-Users a few days ago but am still
waiting for replies. I figured this question might even better suit this
list here, so please allow me to ask it here again

I am trying to use jack for alsa-only applications (jitsi application
image, chromium for videochat in my case) over jack. 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 otherwise empty ~/.asoundrc as follows
	
 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? Can I set pcm device names per
application as defaults?

Thanks for all ideas!
cheers, P