Accidentally hitting play button in lock screen and speakers go off

I'm at my wit's end. This continues to happen. Maybe someone has a solution.

So, if you hit the home button twice while the phone is locked, it brings up the controls for music player. If the play button gets bumped/brushed/breathed on, the music starts playing. And if no headphones are plugged in, it plays through the speakers.

How do I prevent this? Is there a setting?