Keep music app paused in background, bluetooth

iPhone 6+ 64GB

iOS 8.1.3

Bluetooth Dongle (Kinivo BTC450)

Summary: My iPhone 'forgets' what audio it was listening to between the time I get to work and the time I leave work. (8 hours)

Details: For my car commute each day, I listen to the Audible app. On previous iOS versions, I would listen to the app for my commute in (via bluetooth), pause it upon getting to work, use the phone throughout the day, and then at the end of the day I would press play (on my car's bluetooth) and the last played audio would resume (the Audible app in most cases).

With my iPhone 6 however, each time I get into the car and press 'play' on my bluetooth dongle, nothing happens (even though the phone is connected to bluetooth successfully). I have to take the phone out, unlock it, open audible, and select the book I was listening to last and press play. Then it plays over bluetooth. This is a minor annoyance once, but with repetition it becomes annoying! I've checked that the app is able to run in the background, but I cannot figure out what is going wrong.

I've tried some workarounds: if I hold down the bluetooth button to prompt Siri and say 'Play', iTunes Radio will start. If I prompt Siri to start Audible, I will have to unlock my phone.

What am I missing?

Thanks for the help all! Sorry if this has been asked before... I did search, but couldn't find anything. 😟