I made a 500 song playlist on Spotify for my drive across the U.S. and discovered that their "shuffle" was actually random. Or if it was a shuffle algorithm, it

I made a 500 song playlist on Spotify for my drive across the U.S. and discovered that their "shuffle" was actually random. Or if it was a shuffle algorithm, it was a bad one. Whenever I stopped playing (e.g., stopped car for fuel or food), it reshuffled instead of continuing where it left off. As a result, I heard the same 100 songs on that trip.