OH! yes I’m talking about SmartThings on my Samsung cellphone. Thank you for that clarification!
Indeed it’s SmartThings showing up as managing my bluetooth connection, that’s why I was posting here. But now I understand the forum is more for the Automation Platform.
Actually, my Samsung phone remembers the last volume for the headphone jack but NOT if the volume is set to above their “harmful” threshold level. And it’s a good thing in a way, because when I use actual headphones I wouldn’t want that high of volume.
To answer your question about BT connection and/or line-in jack: My car is a 2009, and the bluetooth technology was just in it’s beginning I guess, so I can only have phone conversations through the car’s audio system (and it’s microphone), but the communications to the entertainment system doesn’t allow for music playing.