ive noticed this happen in laguna seca, if you cut the corner into the pits and then keep the throttle on you have an invisible menu.
as you are going into the pits, line the car up early and then don't press any buttons, the computer should drive you in anyway, and then see if the menu appears, there should be a box that pops up about two seconds after the computer takes over, so then, as said above, you have fifteen seconds to pick driver / fuel / tyres.