I just purchased the game yesterday for xbox and went on to my first practice session for Melbourne. I started messing around with the car setup and tried to put the fuel mix to mix 3 (Fast) but it won't let me. I tried while on track as well but when i press up on the d-pad nothing happens. Nothing at all, not even tires come up. So i thought this may have just been because i didn't have enough upgrades or something and that i would get the feature later in the season, but then i went online and it still didn't work. I cannot change the fuel mix at all which is annoying as it leaves me at a disadvantage, especially during the quick game modes which are quite short. Anyone else have this problem or know how to fix it?