Try restarting your phone also check to see haw many background agents you have running. If you get to many live tiles/background agents on the start screen it can freeze all your non native live tiles. Try removing a few live tiles. There is a max number of background agents I want to say 10 but I can remember for sure. You should get a warning when you reach the max number.
Does it matter if the background agents are merely disabled? I have a bunch, but only 2 are turned on at any given time. Nevertheless, I am still having live tile problems.