Why can't I play music in my car with the aux cable plugged into my Samsung S6 Edge Plus?

[AC Question]

I tried to play Spotify on my car stereo today through my Samsung Galaxy S6 Edge Plus with an aux cable, and nothing happened. What am I doing wrong?

 

[srkmagnus]

Make sure you have the radio unit switched to the auxiliary input. Also, make sure your device sound is turned up and the device is not connected via Bluetooth.