I have used the Minelab Safari for a number of years now, and almost always in the sensitivity auto mode. It is very easy to use the noise cancel in this mode with the detector coil right on the ground (as recommended by Andy Sabisch in his book). Recently I have started to adjust the sensitivity mode in manual, selecting either 16 or 17. With those manual settings I seem to be getting more depth, and more silver dimes in hunted out sites. Using the 11" standard coil, I am now faced with another problem. No matter where I place the 11" coil on the ground to noise cancel with a manual setting of 16 or 17, my screen indicates I have iron under my coil. How does one find a spot to noise cancel when in the manual sensitivity mode? I realize I could turn the sensitivity down, and then back up after the noise cancel, but Andy's books says you must noise cancel whenever you change settings??? Has anyone noticed this problem? How can you find a spot anywhere in a park to do a noise cancel without iron being under your coil?? Supposedly, the noise cancel will not work if you have iron under your coil. Help, and thank you.