Was just wondering if you can connect an HDMI cable to your macbook pro in order to mirror it to your TV at anytime, or if the macbook should be closed? Or completely powered down. I notice the screen flickers a few times when I connect it while its open, just not sure if this is ok for it or not. So I have been closing it to connect and then reopening it. But in this state it is only asleep and not actually powered off. Does any of this matter?