Okay on the off chance this is your issue when BigBox becomes unresponsive do you have a mouse connected or just a gamepad and when you say you are plugging in a keyboard and going to ctrl+alt+delete do you have a mouse connected then also? The reason I'm asking is people have had issues with losing focus in the past and a simple left click from the mouse puts the focus back on BigBox which I don't think a keyboard of gamepad will do.