Check the voltage to the unit.
Should be 240 volts (L1 to L2)

I am assuming that all stove top elements have this problem.

Could be that it is just the nature of the beast.

Yes at the wires coming in.

[COLOR="Red"]Be very very careful. You are messing with 240 volts which is lethal.[/COLOR]

The standard color code is
White = Neutral
Black = L1
Red = L2

So there should be 120 volts from white to the black and the red.
Each side should be equal ( if white to black is 117 volts then white to red should also be 117 volts)
And then 240 volts from the black to the red.

Measure it with the elements off.
Then turn on element on high to see if it stays at the same reading/level.
This checks if there is a problem in the electrical supply that is dropping voltage as you put a load on the supply.