The Slingbox is not supported to work with hubs, even though it could work. For this type of connections, we recommend to use a wireless or a power bridge like the SlingLink TURBO.
You can try to use this steps to troubleshoot the issue that you are experiencing with the Slingbox,
If the issue persists, I suggest to hardwired the Slingbox to the router using a regular Ethernet cable no longer than 7ft long, just to confirm if the issue is regarding the hub.
Hope this helps