One of them is trying to light itself from the pilot light. See if the pilot light has gone out, and if so then light it again. If not--then make sure all the burner dials are turned ALL THE WAY off. Usually that's the noise they make when you first turn them on, but they haven't lit yet.
The clicking sound you hear is an electronic igniter. You won't have a pilot light. When you turn the dial to 'ignite' the stove turns on the gas and creates an electronic spark to ignite the gas. Once the gas is lit you need to turn the dial away from 'ignite' and adjust the flame to your desired level.
Make sure the dials are turned completely to the 'off' position. If you still hear the clicking, unplug the stove and call for service.
You can replace the switches, to me it sounds like the problem is due to the spark module which have gone bad. You should make sure the electrode is clean as well as the holes in the burner. Check id the ignition switches are okay. |If everything is in good position then the spark module should be replaced.