Hi. New here. So my problem is with my PSU. It suddenly made a slight pop sound one day when i change places and there was no visual damage on the psu or the mobo. but the psu can no longer be used. after replacing it through warranty, i tried testing it on the mobo only, removing the graphic card and hdd. when i turn on the power button on the psu, the power socket made a buzzing electric noise and the psu is broken again

what's causing this?