It seems that you are having some issues with your Slingbox PRO-HD since although you can connect using the Facebook application, you get a slow connection speed while using the application through www.slingbox.com.
If you can get the connection through the Facebook application, it means that the Slingbox is working in a proper way. In all case, we recommend you to test the connection to your Slingbox PRO-HD using a different web browser that the one you are currently using. We encourage you to check the following article in order to know the information about the supported Operating Systems and web browser versions:
Hope this helps!
I am still having this very same issue. It seems to clear up every now and again but its not working again now. Why can't I watch on the website? I am getting very frustrated about this.
I have a sling box solo and have posted this question before. There is absolutely not a darn thing wrong with my set up or anything else. Now I am in a place where I cannot access facebook but cannot watch my darn TV like I want to. I want this addressed immediately.