I have a Daewoo microwave(KOC 9N7T). Any usage under 30 seconds is fine but >29 seconds, the cooling fan stays on for a good 3 minutes. Hardly a huge issue but a little annoying if you just want your coffee warming up and you hear the cooling fan blast on for a further 3 or 4 mins when the mw was only on for say 30 seconds.. Is there a way to reset or easy fix?