Does the sound stop when you center the right stick?
It is a normal feature of the ST16 / Typhoon H (480) for the machine gun sound if the right stick is in any position other than center when the drone is bound but the motors are not running. If you listen closely, you will hear the sound is coming from the drone motors, not the controller itself. That part is not an issue if all of the assumptions I am making are correct.
But you did not mention your drone model or controller. @h-elsner is correct. We need to confirm the model you are talking about. There are other models in the Yuneec line-up. I'm not certain other models don't have the same feature.
Once we are sure of what model we are talking about we will know how to ask other questions. We need to understand how you are approaching things. We need to know what else you are seeing and hearing. There is data stored in your system. We will help you find it. There are diagnostic tools available. We will help you use them.
@rockstar you have two rockstars of our own offering assistance to you so far, but you have not responded to their requests for more information. There are several members of this forum that can help you solve this issue and any others that show up as long as you interact with us so we can.