Phones via BT sound like crap to me. And extra memory on a Samdung is costly, quirky, and draws down power. Folks get by with them because thats all they have or know. Sometimes the spouse will play an XM show via USB which is OK. I hate it when my background music gets interrupted by a marketing phone call.
I Like to use iTunes to throw a playlist of 10-15 hours of favorite tunes on either a iPod touch or SD card and let it run. I never have run across a format problem. I don't like to be driving distracted and picking through menus, so I only load songs I like ... and its easy to skip one or two songs via the steering wheel buttons. I also have a retired iPhone I use as an iPod. All work fine in the 2016 RAM, even the second gen touch if I recall. I usually run off the SD card when in the RAM. Those iPod touches are durable, I have one in daily use for 10 or so years now. If I'm in the mood for something new or different, I listen to the radio. Radio has upped their game over the bast few years.
So if all you want to have is some background music, its more or less plug and play.
Otherwise a subscription to apple music and a iPhone connected via USB (or a touch with a mobil hot spot) is all I need. ATT sells a well performing hotspot if anyone cares. Dunno about you guys, by my iPhone gets kinda warm with the hot spot activated in low signal areas.