Refrigerator noise

My fridge is a tall free-standing unit with a fridge-freezer underneath.
It makes a loud humming noise which stops when I push the on the doors of
the fridge or tilt it in any given direction.
Any ideas will be gratefully received.

Sounds like a buzz. This happens when vibrating refrigerant lines touch each
other or the edge of a tray, cabinet, or even the back wall and buzz. You
can usually solve this yourself by observing exactly where it is coming from
and adjust the lines or wedge pieces of rubber between them to stop the
sound. The lines can be gently bent but only slightly.