Random songs playing when I plug into my car

[NothingSpexial]

So this doesn’t happen to me but this happens to my dad. He usually just plays a radio on Spotify for Spanish music but sometimes he’ll go into his car and Taylor swift starts playing for no reason. He doesn’t have premium and he hates it when this happens. It’s never happened to me but it’ll be playing his radio and then when he connects to his car again it starts playing Taylor swift again.