JACK notes

ALSA handles hardware

Pulse Interconnects it.

Disable pulse starting before using JACK from startup menu

aplay -l to check alsa output channels

arecord -l alsa input channels

pactl list to check pulse

alsa info in /proc/asound

Can't see soundcards as user but can with root. Try adding user to audio group. Works

For each card run

alsa_in -d hw:0 Card0

alsa_out -d hw:0 Card0

These now appear in connect panel of qjackctl

"system" is the computer (I think)

way to test Alsa outputs: speaker-test -Dfront:AudioPCI_2 -c2 -twav

What keeps starting pulse?

disabled in startup applications

autospawn = no in both

~/.pulse/client.conf and /etc/pulse/client.conf

If it is killed it restarts.

This doesn't happen on the console Mate session only the X2go one

Must be started by X2go somehow

Edit x2go settings to not use audio (session preferences)



The place where the service is running needs firewall modification to allow port 3000 upd through

Only one system can connect to this

Multiple services can be run but results in multiple jackds




had to create link in /usr/include python3.6 -> python3.6m

Account and realtime

check /etc/security/limits.d/95-jack.conf

this will use group jackuser and give it rtprio

useradd jack

passwd jack


usermod -a -G jackuser jack


control centre-> firewall

add port 3000 udp

both runtime and permanent tabs at top

this is primarily for slaves to receive incoming connections


jackd -R -d netone

edit /etc/group

add jack to audio group to allow access to alsa device


jack_netsource -H amberslave -N AmberSlave -o 1 -i 1

run one of these for every slave

edit /etc/group

add jack to audio group to allow access to alsa device


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Topic revision: r16 - 17 Oct 2020 - BarryGreen

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