Haptics don't play in background when bluetooth headphones are connected to Apple Watch

I have a watchOS 3 workout app that uses haptic notifications. It setup correctly to run a workout session and haptics work when running in the background. However, if bluetooth headphones are connected to the apple watch, then you only get the haptic vibration OR the audio chime for the haptic, depending on whether the app is currently showing on the watch face or running in background.


Here's how I'm playing the haptic:

WKInterfaceDevice.current().play(.notification)


Here are the details:


Apple Watch Nike+ Unpaired to Headphones:

Haptic and chime sound activate regardless of whether the watch face is on or off. Chime sound is loud and clear.


Apple Watch Nike+ Paired to Bluetooth Headphones:

Haptic only active if watch face is on, audio chime is off. Audio chime is on when watch face is off, haptic is off. Chime sound is loud and clear.


I tested the app pairing the Apple Watch separately with the Platronic Backbeat Go 2 (released 7/2013) and the Bose QuietControl 30 (released 10/2016). The results were the same.


Anyone know if this is a limitation of watchOS 3, a bug, or is there something else I need to be doing?


Thanks,

Jeff