When using GPS over bluetooth in car, play music plays but I don't want it to

[mcaspe1]

When I'm using my gps in my car over the car's stereo, connected by bluetooth for turn by turn directions, Google play music automatically starts and can't be turned off without effecting the sound from the GPS. Sometimes I don't want to listen to music the same time I'm using the GPS. Very frustrating. I can't find a work around. Can anyone help?