I have used my Safari for a few weeks now and found good silver. I used it on the Auto Sen. and it was stable. I started playing with the manual sen. and the machine started talking alot. When I got a good coin signal on auto mode , I adjusted the sen. manually and ran the coil over the coin. The tone was louder which worries me because the tone on auto was quiet at about 4". I am I missing deeper targets on Auto mode? Over the same coin I changed the sen. to 10 before the machine responded like it was on auto. mode. Setting 20, forget about it! At about setting 14 the safari made less noise but I wasn't sure if the extra sounds were false. Anyhow, what are your experiences with man. vs auto mode?