[Client] Mouse sensitivity bug

Over the past few days I've experienced a constant bug every time I start a game that my mouse sensitivity shoots all the way down to the lowest setting within my computer. It always happens the same way: everyone picks their champs, the client closes and the loading screen comes up. My mouse goes from it's normal speed to it's slowest setting. This doesn't happen playing any other game. I can fix this by going into my mouse setting in my computer and bumping it back up to normal, but this happens every time making league a pain to play. Fortunately it doesn't seem to have affected my during the game once it's fixed but I was wondering what I can do to fix it.