I have the same problem with my Slingbox Pro HD since all MPEG-2 channels were terminated in January 2012.
Even uncoded MPEG-4 channels like DR1 does not shop properly. The picture updates every 1-5 seconds but is otherwis frozen.
It is not a bandwith problem since the same applies on my LAN showing 8000+ kbps throughput. I am using an external tuner and the signal is perfect on an attached TV set.
I suspect we need a firmware update before the Slingbox Pro HD will work properly in Denmark again.