iPhone Playing Music w/o Any Open Apps

This happens when I connect via Bluetooth to my stereo at home or in the truck.

After the Bluetooth connection is made, the iPhone begins playing music. Sometimes this is from the library if I had been previously listening to something from the library (i.e., the iPhone picks up where I left off). It does this w/o having the Music app. open.

Right now, however, my iPhone is streaming music from Radio Classique in Paris. (If you like classical music, it's a great station. ;-)) The Radio Classique app. is not open on my iPhone. In fact, no apps are open on my iPhone, but the music is nevertheless streaming.

This has happened before on my iPad as well. I think maybe I accidentally pressed the "play" button on the wireless keyboard and the iPad began playing (via its speakers), although the Music app. was not opened.

Anyway, it's manageable, but I just wanted to report it.

Cheers, all!