Comment 10 for bug 1877194

This behavior particularly affects Raspberry Pis, where USB is the only bus available for a lot of devices and treating this as "hotplug" gives wrong results.

That doesn't mean the default should change for pulseaudio on the desktop in general, but should somehow be treated in a hardware-specific manner.

I would suggest making /etc/pulse/default.pa key its loading of module-switch-on-connect on the absence of a flag file, which could then be provided by raspberry pi images.

I'm going to open a task on ubuntu-settings for the moment, since it provides ubuntu-raspi-settings that seems the most likely existing package to attach the raspi side of this to.