Freezer making loud buzzing or humming noise from the rear.

Safety first: Unplug the freezer before touching the compressor or condenser.

• Check levelling: Ensure the freezer is level and all feet are firmly on the floor. Adjust the front feet as needed.
• Inspect compressor mounts: At the rear, check the rubber grommets under the compressor mounting brackets. Tighten loose screws and replace compressor mounting grommets if perished.
• Secure condenser and panels: Make sure the condenser coil and rear metal panel are not rattling against the cabinet. Gently bend or pad any contact points.

If the compressor itself is internally noisy (knocking or metallic sounds), it may be failing and should be assessed by a refrigeration technician.