navigation screen related questions

[virusx1]

I am sorry I keep posting every single question. I am just curious if they are just normal or something wrong with my car only.for 07 m35x, whenever I want to turn on AC I always have to push Auto button first then control the way I want. AC button light is not on when I push it when climate control is off. Also whenever I finish talking on blue tooth, the screen goes to the map not returning to where I was right before talking such as radio screen and so on.I don't know if it's way it is, but I feel very bumpier than I expect whenever I go through potholes and stuff, I don't know if suspension is lower than other cars or tires are thin to be that way or something. In other words, my feet feel everys surface condition when I am driving, pushing acc, pushing break and so on. Also, is it better to get synthetic one when I change oil? and should I change filter everytime I change oil? Thank you for reading ^^