I have two sources and I want to run them both to my Vista MCE. When I set up the digital antenna, I get a great HD signal. If I then go back and set up Cable I get all my channels just fine also. However, it wont let me do both. If I first go in to set up my digital antenna it says: Problem is, after I set up the other TV source (cable) if I try and go back and set up the digital antenna, I lose all my cable channels. Why does Vista MC say this if it doesn't actually give you a way to go back and set up the digital antenna afterwards?