I have a Sharp R-1500 that was sparking from the "wave guard cover" and actually burnt a small hole through it. What could the problem be and is it worth repairing or just replace the microwave. The manufacturing date is September 2003. Thanks for any advice.:)

What a lot of people dont realize is food splatters left in a microwave cavity continue to cook everytime the microwave is used.and a little spec of grease or food left in it long enough will actually burn a hole somewhere its always a good idea to wipe down the interior after X number of uses