I took the AT Pro back out to the iron laden beach that I had much luck with about ten days ago. It looked like about a foot of sand had come back so I wasn't expecting as many targets. It was a brutal few hours. I tried lots of combinations of settings - both standard and pro modes, sensitivity from one bar to about three or four, iron disc 25, 35, 40, iron audio both on and off. I auto ground balanced several times. I couldn't get the unit to stop bell toning on iron in standard, regardless of how low I set the sens. When the numbers jumped all over I knew it was iron, but even when the numbers were steady in the mid 80's it was iron. Last time out there lowering the sens really helped. In Pro mode the amount of noise it made was making it tough to pick out a clean hit. I was lost out there today. Almost pulled out the Excal but figured it wasn't gonna be my day and drove home. This is a tough beach to hunt but the rewards usually make it worth the effort.