An update to my comment above. I've now got it working properly. I deleted app then re-downloaded it. I then noticed somewhere on this forum that they had the same problem which was cured by altering the port forwarding on their router, even though it worked fine before the update. I have two routers in my house. I changed to the other router and now everything works fine. So I would assume it is to do with the port forwarding in my case anyway. This is the link to the other thread https://community.sling.com/message/54561
What I understand from your post, is that you're not getting video from the iPad app.
In this case, besides uninstall and download the application back, you can try the following link: