Has any one had this problem: When i turn off my Xbox, the green lights dissapear but the Xbox is still on. It loses signal on the screen but it makes a noise as if it is on. The power adapter also shows the green light as apposed to the orange light whch indicates that it is on. If i unplug it at the back i get a brief flash of 3 red rings... But then it works fine if i plug it in again Any help??