I was digging today, found a sliver of aluminum siding, and the Pro Pointer won't read it on the tip of the PP. The sides do, yet I have to physically contact it onto the sides, but it sings nicely. I did a good job of cleaning the tip off, installed a new battery, and it still tested the same. I did an air test on some coins with it and maybe it's paranoia, it seems that the sides are more sensitive to the coins than to the tip as well. Shouldn't the tip logically be the hottest and most sensitive zone? It is strange that I can't at least get a detection when pressing the sliver of alum to the tip, when it reads fine on the sides. Problem? Shouldn't the tip be even more sensitive? martin