Our Kitchenaid KHMS2040 microwave has been making a strange noise recently. It sounds like a shofar or distant trumpet is being blown. As far as I can tell the microwave is cooking just fine, and the noise does not happen every time we use it, but it has been happening Our Kitchenaid KHMS2040 microwave has been making a strange noise recently. It sounds like a shofar or distant trumpet is being blown. As far as I can tell the microwave is cooking just fine, and the noise does not happen every time we use it, but it has been happening more often. often.

William Miller

• 9179 Answers
• Posted on Jan 05, 2007

SOURCE: GE Microwave problems after HV capacitor replacement???

The rectifier diode could indeed be bad. But first I would want to know what value (in uF) the old one was and what is the value of the new one? If they're too far off, the difference in the capacitive reactance could throw off the "tuning" of the circuit. The uF value of the capacitor is optimized in relation to the other components used in the system. Of course, you'd also want to be sure your new cap is at or slightly above the working voltage rating of the old one, too.

SOURCE: Vibrating noise when cooking

In order to try to set your mind at ease I will have to explain the Basics on how a Microwave Oven Functions.
When a Microwave Oven is set to COOK ...START. It cooks at 100%. There is no lowering of the heat as with a Range ( Cook Top) Control. So in order to do the other things such as DEFROST, WARM, or anything other than 100% COOK. A COOK ON- COOK OFF system was utilized. To DEFROST, the Microve COOKS at 100% for 30% of the TIME, then IDLES for 70% of the TIME. COOK ON 30% of the TIME, COOK OFF 70% of the TIME = DEFROST This is why you can hear the CYCLE. More power is required during the ON CYCLE, thus the lower vibration. The Vibration occurs when the High Voltage Transformer is turned ON ( COOK ON).
The VIBRATION seems to have got louder with age. This is somewhat normal as there is a vibration from the High Voltage Transformer present every time the Microwave is used. screws and other metal parts seem to get loose with this vibration. There is no solution, unless you can tighten EVERY screw, nut, and bolt in the unit.
Sorry!

William Miller

• 9179 Answers
• Posted on Feb 25, 2008

SOURCE: Microwave oven has become very noisy

Oh, this is a UK/European model...

I have no info on that, so your best bet is to contact Panasonic UK:
http://www.panasonic.co.uk/customer-Support/index.asp


Good luck.

We're happy to help and we appreciate your thoughtful rating of our answer.

SOURCE: Kitchenaid builtin microwave buzzing

I would recommend changing the diodes as well. This will usually take care of the problem.

tom wright

• 219 Answers
• Posted on May 15, 2009

SOURCE: Maytag MMV4205BA microwave buzz/grind when operating then no power

you may have some arching inside where your magnatron is located.If you open the door on the right middle part there is a silverplate on the wall .If it is burned you may need to replace magnatron.if you do not seee burn marks it may still be the magnatron hope.that would be the only possible thing that would make the noise other then the mtor plate out of place.