Stuttering Ingame & On Loading

Wondering if anyone else has come across this issue on PC (Steam) and if there is a solution to it because i really cant find one.

I have two instances of stuttering that occur;

1: On the single player campaign, when you select a mission it stutters an awful lot before the cut scene even begins to play, and it does this before every cut scene.

2: When loaded into a multiplayer game for the first like 10-15 seconds the game will seem unstable and stutter about even though its still says i am getting 140+ FPS.

Thanks to anyone that can help :)