Downdraft Slide-In Range

I have the radiant cooktop (i.e., glass top) version of this range. I've had this same problem since I first purchased this unit. I wondered why no one answered this question, as I check back to see from time to time. I finally contacted Jenn-Air's online support. My conversation was as follows (I'm not entirely sure that the tech support knew what she was talking about, but here you go anyway):

Cidalia C: Hi, my name is Cidalia C. How may I help you?
You: Hello!
You: I have a question regarding my "Downdraft Radiant Cooktop"
Cidalia C: Thank you for contacting Jenn-Air today with your inquiry. What is your question please?
You: None of my burners can simmer-- no matter what the setting, they will boil water!
You: Is there an adjustment that can be made to attenuate the heat?
Cidalia C: What is the model number of your cook top please
You: JED8430ADB
Cidalia C: Thank you. In looking at your burner configuration, the smallest wattage on your unit is 1200. And, unfortunately, there is no way to get a small wattage for your burners. We apologize for the inconvenience.
You: Yes, but the dials are supposed to prevent the full 1200 watts from reaching the burner unless it's on maximum heat, correct?
Cidalia C: Yes, but the burners do not get low enough to be considered simmer burners.
Cidalia C: Did you have any other questions or concerns today?
You: I suppose not.
Cidalia C: Thank you for contacting Jenn-Air. Have a good day!