My Pro-HD is set up at someone else's non-Fios house. The Slingbox can be viewed everywhere on the planet except at my house's Fios. I have an Actiontec router and when I asked Verizon about this, they thought it was the Fios router so they sent me a newer Actiontec router but I still have the exact same problem. I turned off the firewalls on the router and the computer just to see if that was the problem but it made no difference.
Note that I can actually connect to the Slingbox using my Fios router but that's as far as I can get. It says the "bitrate" is 0 kbps and then says that it's dropping the connection because of "poor internet connection" which makes no sense since the internet speeds at the non-Fios house and at my Fios house are lightning fast.
What kills me is that I can watch the slingbox on my phone at home if I use the phone's data plan but when I switch the phone over to my Fios wifi, it doesn't work(?)