Default Bluetooth headset will not launch voice dial of google now

For some reason, pressing the phone button on my Bluetooth headset (Scala Rider), will not launch google now, or any other app on my LG G2. It seems like the phone do not recognize the headset as handsfree kit.
Anyone has an idea how to solve this issue? Iíve checked the headset set with some other phones (GALAXY 3, Optimus G) and it worked fine.


thanks,