We had trouble with noises from the power brick from the beginning. I should have returned it, but after a few minutes it would stop humming and settle in. Well needless to say, 2 years later, now the system doesn't run 20 minutes and shuts down completely. I just bought a brand new Microsoft Brick power supply with the new cord. No humming, but system is still shutting down. No warning, it just dies. After a while it will turn on again, so I am assuming it is overheating. We have no additional funds for a new Xbox. Now Santa's Infinity gift is useless. Any ideas?