My 2016 Buick Verano makes this noise around the engine while off (or at least I can only hear it when it's off). It's like a vibrating noise and will turn on a little bit after opening/closing doors/trunk and locking/unlocking the car. It can do it several times and last only a few seconds. If I do the above whilst it is already making the noise, it will begin making a clicking noise instead for a while until it goes back to the orignal vibration if not interupted and then stop (if it doesn't start again minutes later). Sometimes it only does it (or I only hear it) once and some times it will do it several times while off. What could be causing this noise? Both videos of both noises are inserted which will allow you to hear the noise and the general area of where this noise sounds to be coming from. 

Vibration: https://vimeo.com/609296167

Ticking: https://vimeo.com/609295099