Mention whether rapid cooling, fast freezing or another special mode is active. Those functions can change normal running patterns and help interpret the sound.
What the observation tells you
Also state which doors are open and whether shopping was recently added. A recording pressed against the cabinet exaggerates vibration and can obscure the real character. Do not move the appliance or open panels to place the microphone closer.
A useful next step
Record briefly from a safe normal position and pair it with the compartment symptoms. A sound clip assists assessment but cannot confirm a particular internal component.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.