Every time you switch cars, the surround mix gets broken. It’ll sound compressed and not as 3D as it should. This is especially annoying for those of us who run pretty high end spatial audio rigs. I’ve done countless testing on this. I’ve tested every mode that my Series X is showing me. 5.1 uncompressed, 7.1 uncompressed, Dolby Digital, DTS Digital Surround, Dolby Atmos, DTS:X. I play primarily in first person so this breaks immersion. No good.
Only workaround is to restart the game when you want to switch cars. REALLY ANNOYING.
Easiest way to tell is to apply anti lag turbo to a car and check the cockpit audio. Soon as you switch to something else and switch back to it, the exhaust pops will be more up front. Upon game restart they’ll be more at the back of the car where they belong.