Just watched tnt and discovery each for 5 min and zero freeze/ locking up. Been watching the movie channels all day as well as no issues. If this is happening every weekend for you then it's not a server issue its a ISP issue. Or it's the hardware your using. Cheap boxes will give you crappy results unfortunately.
First how about getting the US version of Cartoon Network instead of the UK version. The UK does not have Adult Swim on their Cartoon Network.
Second it would be nice if the Los Angeles Networks that are already loaded in the list "worked". It would be great to have West coast feeds of the networks.