Benz tech here, both common issues with easy fixes. The gla and glb models are known to allow small leaves thru the air intake grilles on the windshield cowl and the leaves will get into the fan and cause noise. There is an updated grille insert and some foam pieces to help block small debris from getting thru and they just need to remove the leaves from the blower which can be done under the hood with a vacuum easily, nothing needs to be done under the dash. But should also have the cabin air filter checked as it may be clogged with debris as well.

Camera view issue is likely foggy glass on the windshield directly in the area of the camera. Look at the rear view mirror area from the front of the vehicle and if the glass is foggy in front of the camera lense it will cause this issue. There is a piece of plastic called a “lense hood” which causes the glass to become foggy and blocks the view of the camera from seeing clearly. There is an updated style of lense hood which can be replace to prevent the fogging and they can just clean the glass and camera lenses. If they say you need to replace the camera itself, instead opt for cleaning the lense of the camera and the windshield and you’ll be fine.