You either have the sensitivity turned up way to much, or you have a bad unit...first, air test the machine...just like it says in the manual...then, take it out in your yard...you will not most likely be able to turn the sensitivity to 3 o'clock as suggested in the manual...I can not usually turn it above like noonish here in NY without it going nuts...if it continues to chatter constantly, turn the sensitivity down until it stops...if you have to turn it down all the way, I would say you have a bad coil, or a bad machine...change to the 4" coil, and repeat this test...if it acts the same, I would say it is the machine...if it gets better, it is your coil...
Hope this helps...
P.S. You have probably noticed that the manuals are wrong in stating that when you turn on the machine it is in the all-metal mode...well, it is, but it is in the All-Metal DISC. mode...This makes the machine mostly turn on and go...There is no difference between the Land Star and the Cammo-LS electronically...
Happy Hunting,