Linking virtual sound cards in two virtual machines?

I would like to create a virtual audio cable between two libvirt guests such that sound output from guest A goes to sound input on guest B, and vice versa. I figure the solution to this is using something like the pulseaudio's "virtual sink", but I'm not entirely sure what the syntax would look like (fwiw, I'm on Fedora 39, which means libvirt 9.7.0, which means this has to be through libvirt's pulseaudio driver rather than the pipewire driver, since the latter isn't available in 9.7.0). I started by creating a virtual sink (and yes, I realize that's only half the process): pactl load-module module-null-sink sink_name=vaudio0 And adding the following snippet to the domain xml for guest "node1.virt": <audio id='1' type='pulseaudio'> <input name='vaudio0' streamName='node1-in' latency='100'/> <output name='vaudio0' streamName='node1-out' latency='100'/> </audio> But trying to start this guest results in: error: Failed to start domain 'node1.virt' error: internal error: process exited while connecting to monitor: audio: Could not init `pa' audio driver There doesn't appear to be any additional information in /var/log/libvirt/qemu/node1.virt.log. I'm wondering if someone has an example of what this might look like? Thanks, -- Lars Kellogg-Stedman <lars(a)redhat.com&gt;