Gamebreaking FPS Dropping Bug

sorry for the clickbait-esque title but I really want this to gain some traction so that it gets fixed. Since patch 6.20 I've been having a bug where sometimes my game sounds will get amplified, causing a crazy drop in frames. I'm usually at a steady 80-90 FPS but my frames drop to between 1 and 6 FPS (not exaggerating). The game literally freezes sometimes, and this is all happening in the middle of a fight. I'm not sure what triggers it, because it doesn't happen every game. It is not exclusive to one champion. I was looking to see if anyone else was having this problem and I found a link to this. It's months old, from a different patch, and seems to have been exclusive to Mac users, but it is the exact problem that I am having, and I'm on Windows 10. Like I said it doesn't happen in every game (probably about 3/4 of my games right now are affected) but when it happens I cannot play the game at all.