3 years i have used my explorer every chance i get and i like it a lot but one problem i have tried to get by and hit a wall every time is when i use the machine on say a trail or old field it works really good sounds are clear depth good id ok ,but when i get near old foundation holes from the late 1800 to early 1900 the machine makes everything sound the same as or close to silver coins sounds.i have found many ih pennies, a number of seated dimes and a few British coppers, but never once a silver quarter or anything silver when close to the actual cellar of the home, why? after all this time i do not believe that there just not there, it must be rusty nails or some other common debris that sounds like silver coin signals, but thats all i hear is high tones every few inches, there obviously not all coins, so how can i get these signals cleaned up? iron mask wont eliminate them at all because there high tones, the sensitivity doesn't seem to have any affect in man or auto,I've tried the settings for coins and other presets and some home made programs but nothing helps. maybe my hearings bad? I've tried different coils, but that only separates sounds more but not eliminate them. i had one problem i fixed it seems the machine loves rocks and throws a 00 31 signal constantly SO i edit it out but the other chatter i hear is definitely stopping me from good finds. my normal settings are ferrous sounds, gain7, vol6, sens manual 24, fast on, deep on, audio normal,and i use a custom program that blocks out about 1/8 out the left screen and a dot at 00 31 to block out that problem signal from before. thinking about a whites or fisher maybe it will help?