Rider 400 linking to a bluetooth receiver?

Gpz Registered Users Posts: 4
Apprentice Traveler
edited January 2019 in RIDER
I have just purchased a Rider 400 kit. I have a set of custom ear plugs with integral speakers and I connect these with my phone via a small bluetooth receiver. however the Rider 400 will not connect to this device therefore not enabling me to hear the route directions.
What type of Bluetooth device do I need to use with my ear plugs?