FYI: Adding Bluetooth(B.T.) capabilities to a non B.T. GPS.
I own a Garmin Zumo 450 GPS unit and 2 Sena smh10 B.T. helmets communication devices. The Zumo is not a B.T. unit, however it has a 3.5mm output jack for headphones (this is very important)
The bike (K1200lt) has a radio/CD changer, but no MP3 capabilities. The Zumo 450 has a built in MP3.
How to get the GPS voice communication and MP3 player to the B.T. headset?
For as little as (CAD)$50 or (USD)$40 you can accomplish it. This is a lot cheaper than replacing a Zumo GPS (at least $800).
I bought a TaoTronics Bluetooth 5.0 Transmitter and Receiver and I am using it in transmitter mode. The TaoTronics Bluetooth can be connected via a 3.5mm jack, RCA or optical (Toslink). The unit is very small (2.4 x 2.4 x 0.8 inches) and comes with all cables but no charger. A cell phone charger is all what is needed.
The unit can have 2 simultaneous BT device connections (in transmitter mode) and it was easy to connect the 2 Sena. This is great as rider and passenger can listen to the music, use the phone or communicate with others. The pairing was a no brainer.
I would recommend this unit to connect non B.T. devices to a B.T headset. This is Bluetooth version 5.0 and its downward compatible with older B.T. versions.
I also tried it on a TV, and it works well. I used the optical connection from the TV for one reason: I can mute the TV and still receive the sound on the optical port (Pass through). The only drawback is that the volume has to be set using the B.T. speaker controls and not the TV remote control.
There are cheaper versions with no optical input/output. I believe they would work, but it’s up to you to read about it.