Tomma:
I done some research on external mics as they produce a much better sound than the fixed mic in the GoPro. It sounds okay without an external mic but the sound quality is far poorer.
I had the mic hanging from the camera and clipped to my camera bag on the passenger seat.
I should have upped the side windows a bit to eliminate some of the wind noise.
Next up will be the camera mounted on the outside and the mic in car.
Still playing but will get it right eventually