I am not aware of a loud buzzing noise that would be normal in this type of refrigerator. The damper motor will make a very faint humming noise when it opens or closes. The compressor will make a buzzing noise when it is running. These types of noises are not very loud in this type of refrigerator.
You could have ice build-up that is causing the noise. A fan blade could be striking that ice build-up to make a loud buzzing noise. A component problem in the refrigerator could also make this loud buzzing noise. You will normally notice a cooling problem when the refrigerator has one of these failures. Since the refrigerator is under warranty, I recommend that you have it checked by a technician based on your description of a loud buzzing noise. Keep in mind that the technician may have a difficult time diagnosing and repairing a problem if the refrigerator is not making that noise during the service visit. You may consider recording the noise if it intermittent. This may help the technician.
You can call 1-800-469-4663 (1-800-4MY-HOME) to speak with a technical specialist and schedule service if necessary.
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