How do you fix your xbox360 after you changed your digital output to something else and now you receive no video output

Well, first of all, if you receive no video output, nine times out of ten it is not your xbox 360 that needs fixing, but your television. If by chance it is your xbox 360's problem, you should check that it is not making any strange or abnormal noises as that may be a sign that your xbox 360 has an internal problem. If this is the case, the best decision would be to take it to a repair shop, such as Best Buys' Geek Squad, and let them give you the actual problem and fix it.