The refrigerator contains pipes that vibrate slightly when refrigerant is pumped into the system. These pipes must not be blocked or in contact with other pipes or cables. It is also possible for shelves, cupboards and other items in the refrigerator's interior to vibrate when the refrigerator is running.
Try to prevent the noise from originating:
1. Change the refrigerator's location or check that the pipes are not in contact with each other or the wall.
2. Position the refrigerator upright, without leaning it against anything.
3. Adjust the feet.
4. Remove any food from the shelves and then replace it.
5. Check that the containers inside the refrigerator do not hit each other.