Thanks for using our Answers Forum! Sorry to hear that your Slingbox Pro isn't working correctly. Most times when you get the message "Your Slingbox has been disconnected because of a poor Internet connection. Try connecting again." it is something between the router and Slingbox. I have a couple of troubleshooting articles that may help you out:
I'm aware that the first link is for the SOLO, but the troubleshooting is the same for the PRO so it should help you out in terms of your network connection.
The Slingbox Moderation Team