[Client] Black Screen in ARAM Lobby

Twice tonight I've had an issue where I get into the lobby for an ARAM game and the window just goes black. The title bar at the top and the outline of the window itself are still visible, but everything inside it has a Noc ult cast on it. If I wait it out, I will get into game, but that means no trading, no control over runes, masteries, or summoners...

Slightly irksome.