Audio Systems: car stereo/speaker clicking noise, land rover discovery, magnet structure

Question
I have a land rover discovery 2001 and just started yesterday - the there is clicking noise comimg from the speaker of the back passenger door (on the driver's side).  The sounds resembles the sound of the automatic door locking.  What do you think/suggest

Answer
sounds like the speaker's voice coil has become 'out of round', and hitting the magnet structure. if you can get it out, push in the cone slightly, and feel if you feel any touching at all. it should push in and out without any rubbing or even the slightest touching.