Just took delivery - questions

Hi all - just took delivery of my LR Y that is replacing my SR Y (that was totaled after a few weeks), and one concern and one question someone might know of.

Concern - while stopped at a light I noticed there was a very deep pulsing sound every 15 or so seconds. Almost sounds like a bass note. Did not really vibrate, but very noticeable audibly. Very hard to explain, but I’m assuming if it’s happened to you, you’ll know what I mean. Never happened in my SR.

Question - went to stream music through the car and it’s asking me to login which I did not have to do with my SR, any idea what the login would be? (Already tried Tesla login into.)

Any insight is appreciated.