Try rebooting your router (if connected) and all your receivers and see if that helps.
When you run a system test on your receivers what does it say? To get to the test menu press:
MENU>Settings & Help>Settings>Info & Test>Run System Test
When you run a system test on your receivers what does it say? To get to the test menu press:
MENU>Settings & Help>Settings>Info & Test>Run System Test