My car has Apple CarPlay built in, I have my music on a solid state drive. I doesn’t work that well, it seems to be buggy and there haven’t been any updates in three years from GM. I spoke to people at GM, they are clued out. The software comes from somewhere else.
I think that the issue is that I have too much music. It results in indexing problems. I have tried it both with a wire to my phone and using the car’s wifi. It works but the phone’s screen is too small to see the songs or search. So I don’t use it.
Due to these technical issues, I prefer CD’s. I made hundreds just for the car, well thought out track listings. Get the new car and no CD player. GM doesn’t want me using one. Got to look at USB CD players I suppose.