i changed my system psu from 400w to 500w. but whenever i turn my system on, speaker(headphones also) makes humming sound its pretty loud i barely hear the songs i played in my system....both speakers are works fine when it connected to mp3 player or phone..please help me ..i have f&d a520 2.1 speakers..rest all things are works fine..i reinstalled sound driver also..,i dont have sound card..motherboard is intel dg41rq..