[alsa-devel] [alsa-dev] Variable latency issue in alsa-jack-plugins

[Corfu, Valentin (Wind River)]

Hello guys,

I recently encountered a problem about variable latency in alsa-jack-plugin.

I have successfully checked the latency with jack_iodelay in following way:
$ jack_iodelay  &

$ alsaloop -Pjackplug  -Cjackplug  &
$ jack_connect alsa-jack.jackP.998.0:out_000 jack_delay:in
$ jack_connect jack_delay:out alsa-jack.jackC.998.1:in_000
But total roundtrip latency, seems to be variable after each start-up.

Q1: What can be the root cause of this variable latency issue?
Q2: How can I find theoretical latency of the alsa-jack-plugin in both directions (playback - capture) ?

Thanks and Best Regards,
Valentin
Intel GmbH
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