No emails as they arrive - Communications Service suspended (Windows 8.1 Preview)

Hi there. It seems I'm not getting any new emails until I open the Mail app and hit sync, even though I have it configured to "as items arrive". Is anybody else having this problem?

Upon checking the Task Manager, I can see that the Communications Service becomes suspended as soon as I leave the Mail app. I can see why the App would become suspended, but shouldn't the Communications Service keep running all the time?

Any thoughts?