What is it inside the Mini 2 that generates the startup tones on startup? It could be, but I doubt it's going to be, from a transducer because of needing minimal weight, so I'm guessing it's something to do with different voltages through soledoids and making 'em vibrate to get the tones. Click, click, ♫Doo-doo-doot!

Anyone? Anyone? Bueller?

Hi! You might be better off posting your question in the 'products' section of this forum.  That is way more active.    -   https://forum.dji.com/forum-129-1.html

I am pretty sure it is the ESC (Electronic Speed Controller) Brushless motors like on drones need an controller for them unlike conventional brushed motors. The sound you are hearing is the ESCs on all four motors initalizing.

https://en.wikipedia.org/wiki/Electronic_speed_control

As for the clicking sound you are hearing, I know exactly what you are talking about. I honestly don't really know. My best guess is that it is the camera stabilizer/gimbal doing a self-diagnosis.