sorry forgot to mention
another thing i noticed is when the PC shutsdown / restarts my electricfan on my room. also gets affected.
i replaced my wall socket thingking it was just loose but ddnt fix the problem. i tried other AVR. i'm suspecting my PSU has the problem (not sure)
because when i system restore the PC it seems it gets fixed. now i'm really confused if its a hardware problem but most likely its software prob. i think.