@Bushlake 

Hi,
Thank you for the case report. In this case, please check if the Tapo C310 is sitting in an open area, and if not, you can try to change the camera's location if possible.
And please check if the Tapo C310 is closer to some electric devices, and if yes, you can try to move the electric devices away from the camera.

If the problem remains, can you share the video recorded on the camera's Live View page manually when the microphone sets to maximum with us? And share the video that shows the problem and recorded with your other phones when the microphone sets to the maximum with us? We will further analyze the issue with two videos.
And you can send me the link to download the videos via private message.

Have a nice day!