I can answer few with my experience. I may be wrong but still here is what my experience says
1- when I hit the brake it ticks or when I release it, it ticks.
Ans: Thats because whenever you hit the brake the hybrid battery charges with it due to which you are feeling that sound, I too felt it in start and than get to know about the whole mechanism and never worried about it again
2- there's a fade humming sound coming from the AC (like the non tuned radio channel). What could be that?
Ans: No problem its built in like this and the sound you're feeling is because when the car is running on battery it is producing approx no noise and the only noise you could hear is from AC.
3- what is the music on/of button on the right side below the side mirrors adjustment panel. way below that panel, above hood opening latch
Ans: That button is for pedestrians alert, when the car is running on battery it produces no sound hence this will not alert any pedestrians and you might hit someone due to this, so if you switch it ON it will produce artificial sound just like the sound of a running car which will alert pedestrians. If you want to switch it off, you can. When the light on this button is ON that means the sound will generate on battery running and when there's no light that means its switched off.
4- it's very low. Currently have 14" tire size. What's the best way to increase the height.
Ans: Do increase tyre size if the problem is severe. Mine also came with 14 inches tyres but after facing the same problem as yours I've installed 15 inches and a bit bigger than the preferred size tyres which solved my problem of hitting the bumps and speed breakers. I've installed 185/70/15 whereas recommended size is I guess 170/65/15. But keep in mind increasing tyre size will reduce petrol average by 1-2 kmpl.
I hope this Info will clear most of your concerns. Thanks
