Time goes too fast/slow in game

Hello, here is my problem:

When i start game, time starts from 0:00, but it goes a bit faster/slower than for other players. For example during 20th minute of the game my time is 19:07. It also bugs skills cooldowns, shows me that they are available while i cant use them for few seconds until they're actually available. Same goes with Drake, Baron, and Blue/Red Buff timers. Sometimes my character speeds up and slows down, same like animations, but its fairy playable. The main problem is with skills cooldown and timers. What can I do about it?