275 My 275 Nav keeps beeping at me for 2mins then stops.

Heyo, So whenever I start driving and go above 15mph my car starts beeping at me which gets more aggressive after 30 or so seconds but then it completely stops after around 2 mins and I never hear from it again until after the engine has turned off and i start driving again.

With what it sounds like and then getting more progressive I thought it would be something to do with seatbelts but the beeping happens even when all seatbelts are plugged in.

Any ideas?