Ear breaking audio bug.

Why does my audio do this? This short jumpy and staticy noise has always been a part of league for me. In about 10% of my games the audio normally does this. Generally i can fix this by turning all sounds off and on but recently it has spread to my recordings too. I wanna take highlights but when i do my frames drop to 8 and the audio bugs out. *this is with the built in recording software.