On Xbox One, in split screen, every time you choose a new car, it will always be at least one race before you get sound on that vehicle. The first race is always silent.
For example:
RACE 1:
Driver A picks 911, Driver B Picks Corvette
Neither player has engine noises.
Race 2: Both driver pick the same car
Both cars have engine noises.
Race 3: Driver A picks the 911 again, driver b switches to a BMW.
Driver A has sound, driver b has no sound.
It doesn’t matter the car or track you pick. Rarely sound will never return but almost always sound is missing for the first race you do with any specific car.
Other split screen issues:
No way to pick non rolling starts (not sure if feature or bug, hope it is a bug(
No way to specific weather (feature or bug)
Sometimes you will get stuck in a loop telling you to homologate your car, even if it is homologated. Will investigate further to find the exact message next time it pops up.