Audio Through USB

Using netJACK2

NOTE: This requires v1.4 or later.

First, connect the MOD Duo to your PC via usb cable.
Make sure to open port 19000 on your firewall. If you use Linux with ufw, you can use:

sudo ufw allow 19000

Then, ssh into the Duo, and run:

touch /data/enable-netmanager
systemctl start jack-netmanager

NOTE: You only need to run this command once.
The next the Duo boots, jack-netmanager will be loaded by default.
Delete the '/data/enable-netmanager' file inside the Duo to remove this auto-start feature.

Now run jackd on your own computer (connected to the Duo via USB), like this:

jackd -R -P 80 -d net -a 192.168.51.1 --opus -C 2 -P 2 -i 1 -o 1 -l 4 -n mod-slave -s

Adjust the parameters as needed, but keep the client name as 'mod-slave'.

Parameters explained

-R	Use realtime scheduling, enabled by default
-P	Set the realtime scheduling priority, in this case 80
-d	JACK backend, in this case the "net" driver
-a	Multicast address, in this case the IP address of the MOD Duo
--opus	Use Opus compression, optional as it is not needed, the USB connection should be able to handle raw data
-C	Number of audio input ports on the slave. This determines the number of output ports on the MOD Duo, marked as "Hardware Audio To Slave" ports in the web interface.
-P	Number of audio output ports on the slave. This determines the number of input ports on the MOD Duo, marked as "Hardware Audio From Slave" ports in the web interface.