Udev and Pulse

This is about using a USB DAC (digital-analog audio converter) in Sailfish OS. It is an external device that records analog signals via USB, often used in music production and art.

You need to become root:

# devel-su
 #echo 'ATTRS{id}=="mtsndcard", ENV{PULSE_IGNORE}="1"' > /etc/udev/rules.d/89-pulseaudio-usb.rules
 cd /etc/pulse/xpolicy.conf.d
 mv usbaudio.conf.disabled usbaudio.conf
 pactl load-module module-udev-detect

 

The last command can be persisted with a systemd unit THIS IS NOT finished.

vi /etc/systemd/system/pulse_udev.service

[Unit]
Description=udev pactl to start usb dac

[Service]
Type=oneshot
ExecStart=/usr/bin/pactl load-module module-udev-detect

[Install]
WantedBy=multi-user.target

Article discussion: USB DAC playback on Sailfish OS Forum