I have heard that water or dirt on the ignitors can do this. Try shutting off the power to the stove for a while and cleaning, then drying, everything really well.
Thanks Steve. I gave the stove top a good cleaning yesterday. I guess that did it. I'll keep the power off of another few hours.
Using an old stiff toothbrush on the holes of the burners and the ignitor holes works well, but use it dry. Liquid is the main enemy of the gas range!