Slow virgl with spice

I have several VMs set up to use virtio with virglrenderer and checking glxinfo suggests that is working.

If I connect to the VM via SDL or GTK without spice then the desktop runs at ~60fps and glxgears gives me ~700fps.
If I connect to the same VMs with any Spice client then the desktop feels like it is stuck around 30fps and glxgears gives me ~38fps.

In all the above cases glxgears reports using virgl as it should.

Is this massive performance drop expected with Spice? I don’t particularly care about high performance 3D in these VMs but I had hoped to be able to use the VM desktop at 60fps+.

The host is Intel Comet Lake.

This is magically fixed after some updates from the repos.