i have an xbox360 slim (i think) and i usually play it on the family flat screen big tv but recently i moved into my room on to a small tv and switched the HDMI cord for the standard cord that came with my console.. when i put in a dvd it said something like a critical system memory unit has been removed, the console shall now restart. it does this every time i switch cords and watch dvds and usually i just keep on trying to watch the dvd untill it works... i just want to know why it does this and some dvds don't work after i do theu usuall stuff....