Best to use headphones to listen to this video.
Audio testing the Yi 4K+ with both the Yi Gimbal and EVO GP-Pro gimbal. The right audio channel mic is on the right hand side of the camera. When the camera is mounted in a gimbal, the right mic is pressed up against the gimbal motor, so you will hear gimbal noise.
In this test with the Yi Gimbal, the gimbal motor sound is pretty much totally eliminated when the camera is in the alternate configuration, where the gimbal arm is reversed, and the other side of the camera (with no mic) is pressed up against the gimbal motor.
The camera on the EVO GP-Pro gimbal cannot be mounted in the alternate configuration because the bracket to secure the camera doesn't go over the camera, and must be secured by a rubber band.
I've also tried muting the right channel audio in this video in post so you can see the difference, and see how much gimbal motor noise is coming from the mic that is pressed up against the gimbal.
In a future test, I plan to use an external mic to see if all the gimbal motor noise can be eliminated.
Latest up to date discussion and information about the Yi 4K+ action camera: https://www.reddit.com/r/yi4kplus/