I have just had my microwave stop working. It sounded perfectly normal, but would not heat anything. I had to look long and hard to find a repair place that handled microwaves and then found J&H Appliance.
They were very helpful. Also, I was surprised to find that my repair (a Magnetron replacement) was covered under warranty since the microwave was only 7 years old.
If yours fails, these guys might be good resource to check out.
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