What a headache!

I love the way this microwave looks and works BUT it has not been reliable.  When it was 3 or 4 months old, it quit working.  The repairman discovered the internal wiring had been done incorrectly, causing wires to come in contact with something hot and burn through.  Not exactly a confidence-inspiring thing.

Now - if I boil water on my stove, the fan will randomly turn itself on and off.  I can't shut the fan off with the button.  The problem has gotten steadily worse.  It used to stop after an hour or so, but now it has been going on for four days!  I have to unplug it.  It is only three years old and I have to call for repair a second time?  Not good!