Hey my xbox turning on and off via power button

My xbox power button is sometime clicking itself couple of times when the xbox is on and it's not overheating or anything like that because when I unplugged main circuit board responsible for power button everything is working and it's not clicking itself, please help me because I would love to have everything working in case a would want to sell it also my xbox is making a weird sound similar to taping a glass cup with metal and I don't know why