subwoofer and amp

Everytime I start my 2002 Range Rover the sub-woofer makes a clicking noise as if the amp is giving the sub some power but the sub-woofer does not work. When I am driving or even at a stand still the clicking continues and occurs every 5 minutes or so. What could be the problem? Should I buy and new sub-woofer and amp set or could it be an wiring problem? I would just go to a dealer and have them check it out but, because I am in the military stationed in Sicily there are not many options on this island. Please give me some insight. Thank you for your time in advance.

sounds like little johnny has been listening to too much dirty south rap. i bet the sub is popped. try taking it apart and playing the sub through another amplifier at a low volume just to test it and see if it works ... if it crackles or does nothing... don't let that boy drive your truck anymore.