"Looks like you're listening on another device"
My iPhone 6 Plus regularly displays the message "looks like you're listening on another device" and pauses the music while I'm playing music through a Definitive Technology bluetooth speaker while connected to wifi at work. The problem also occurs, albeit less frequently, when using AirPlay and AppleTV while connected to my home wifi. The problem happens whether or not the phone is connected to power. Any suggestions for correcting the issue is appreciated. Thanks.
iPhone 6 Plus, iOS 9.0.2