Smartphone voice output Navigation via Bluetooth coupling

Hello together, maybe you can help me. I’m in despair about the voice output. Bluetooth and phone calls work fine with my Android mobile phone. I thought that it would have to work if I can use the smartphone to output the directions also via the car speakers. No matter if I use Google Maps,Sygic,Telmapnavigator – I just can’t get the output via the car speakers I can enter what I want in the media output configuration of the mobile phone, it just doesn’t work. Can one of you help me or can you not get it? Beautiful Easter to all of you. LG Volker