apu bug fix
apu bug fix

shaggytwodope/nes,sheenobu/nes,Rosmianto/nes,horryq/nes,sunclx/nes,fogleman/nes,xuxiandi/nes,trigrass2/nes,tastynoodle/nes,wangweijia/nes,Esmidth/nes,liqingzhu/nes,Endika/nes,EmuxEvans/nes,UIKit0/nes,insionng/nes