Sleepy Pipewire

[TheMerret]

Quickshell's pipewire service gives current volume only after linking any node to the default sink node.
My quickshell version: quickshell pre-release, revision 67524f9d8e4ac5e09ea4427e11f2284e6a6f93fe, distributed by: Official-Nix-Flake. I use quickshell config from this repo: https://github.com/SirEthanator/Quickshell-WIP. Here is the snippet:

  readonly property PwNode audioNode: Pipewire.defaultAudioSink;
  PwObjectTracker { objects: [ root.audioNode ] }
  readonly property int volume: Math.round(audioNode?.audio.volume * 100);

I start quickshell from niri's config spawn at startup. Then using commands like wpctl set-volume @DEFAULT_AUDIO_SINK@ 0.1 producing no updates on pipewire default Audio node status.
But when I connect something to default sink ports (launching pavucontrol, playing video using mpv, manually in helvum), setting volume gives expexted PwNode updates in quickshell.
Now at startup I run pw-loopback and kill it immediately, but I think that is just workaround for above unexpected behaviour.
If there any trace methods to find the root problem?