Ok i have already had an RMA accepted via corsair for my psu Hx850, Its been whining very lowly when powered down. But i have been putting off sending it , seeing as its not that serious. I have been switching the pc off at night by the back of the pc on the psu switch. Today i pressed it to on and there was a low bang noise!!. I turned it to off again and back to on and its come on and is working fine. What is going on guys !!!! should i send it to them