It would sound like you may want to set up "port forwarding" on both the router the Slingbox is connect to, as well as the router at your remote location. Here are some of Support Articles that explain "port forwarding":
If you are port forwarding a Slingbox other than a Slingbox 350 or 500, you will want to use either port number 5001, 5002, 443, or 8080. Port forwarding of a Slingbox 350 or 500 should not be necessary, however their port number would be 5201.
Get back in touch with us if that doesn't work!
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