Hi. I'm Smitty. I am a professional appliance repair consultant here to help you diagnose, and repair, your appliance.
Unfortunately the humming is the sound of the motor under more strain. This is what normally happens when fans wear out.
You can have a new motor put into it but the cost is prohibitive. You could get a brand new one for less.
Sorry for the bad news. I wish it could be better.
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