my game crashes at the start of every game but then works fine after i restart it.

so i am not really sure what is going on, at the moment whenever i start up a league game (mainly on summoners rift) it plays fine for a few minutes and then it crashes, the weird part is that whenever i load it back up after the crash it works fine and i don't have any issues with it for the rest of the game. Now i have tried hextech repair tool as well as verifying the integrity of the files and neither seems to have done anything. i have not tried reinstalling league and frankly i don't wont to do that if i don't have to. If anybody else has been experiencing this issue please post below and let me know what you did to fix it if you have fixed it.