So everything works properly for 2 of the users on a site I'm setting up, except chats and shouts that the other 2 users post aren't received without manually reloading the page. Those first 2 users can chat with each other normally, but have to reload to see chats from the other two. I'm not seeing any errors with dev mode, or in the logs (mongo, nginx). I've tried about everything I can think of, deleting sessions, removing plugins, different browsers. We only have 4 members, so I don't know if it would affect more than just those two users.
To be clear, myself and another user can chat normally, but need to reload the page to see chats from the other two. Websockets seem to be working correctly. The other two can get notifications for non-chat things, they can send chats, and they can receive chats, it's just their sent chats that don't seem to be updating dynamically.
Configs are here
These two users were able to chat normally earlier today, but only briefly, then the problems started again. There wasn't anything that I had done at that point, so I'm at a loss.