Ok, when detecting in my yard with my new 705, I setup my nc and gb, detect in am mode, pp and my pp stays on and the audio keeps on even after I move the coil away. Reset to PF, tried it again, same thing. Tried another spot, worked fine. Moved to another spot, detected target, pp, and pp stayed on again. Reset nc and gb, then seemed to work ok at that spot. Then I hit the tracking button and it seemed to work ok no matter which spot I tried. Any clues to why the PP would lock on and stay on?