This is the first time that this happened, as I turned the engine on with Ready light, the beeping noise started. It would not stop until I turn the car off. When I turned the car back on again, everything is normal again.
I can see no warning lights on the dashboard except for the seatbelt light (although I have not even moved).
Has anyone else experienced this strange sound yet?
Video here
https://vimeo.com/234181990