0.4.81/82 (0.5 pre) Forgets Loopback Volume Levels on Restart

This did not happen on 0.4.17.

I have virtual sinks set up in my pipewire.conf, like this:

context.modules = [
    {
        name = libpipewire-module-loopback
        args = {
            node.name = "game"
            node.description = "Game"
            audio.channels = 2
            audio.position = [ FL FR ]
            capture.props = {
                media.class = Audio/Sink
            }
            playback.props = {
                node.passive = true
            }
        }
    }
    ...

When I change the volume through the KDE Plasma panel, to say 50%, I can verify that stream-properties gets updated properly for that sink:

[stream-properties]
Audio/Sink:media.name:Game\sinput={"mute":false, "channelVolumes":[0.125000, 0.125000], "volume":1.000000, "channelMap":["FL", "FR"]}

If I restart pipewire (or my system though), it immediately gets reset to 100% and overwritten:

[stream-properties]
Audio/Sink:media.name:Game\sinput={"channelVolumes":[1.000000, 1.000000], "channelMap":["FL", "FR"], "volume":1.000000, "mute":false}

Volume is properly restored for hardware sinks, but not the virtual ones. I figured maybe this is a regression in the 0.5 pre releases.

If it helps, I'm using Ubuntu 23.10. I built/packaged the newer pipewire and wireplumber for myself.