[CLIENT] Connexion Timed Out before and after game

Hi, When I'm not in a game, I get these connexion timed out message, after them I don't receive friend invitation or if i'm already in queue, I can't see the accept/decline window, so I get kicked out. It is seriously annoying since this happens every 4 minutes, it's almost impossible to do a dominion, since I need to reboot my client every 4 minutes if I don't get in a game. I also can't see the stats screen and chat with my team after a game. Curiously, its happens less after game when it's a win. I already tried to delete the LoLClient files in roaming/appdate and to disable my IPV6. I'm on Windows 8.1. Thanks for helping, this is really ruining the game and annoying my friends.