User-Agent: Mozilla/5.0 (Mobile; rv:41.0) Gecko/41.0 Firefox/41.0 While using apple earbuds in the music app, pressing the inline button once pauses the music as expected but then the headphones appear disconnected. Similarly with the podcast app the "pause" button disconnects the headphones without pausing the podcast, and it continues to play through the speaker instead.
This seems like an audio channel issue, but let's start with Gaia::Music.
Moving to Audio Channel per comment 1. Music doesn't do anything special with this.