The meter will ALWAYS move with the tones.... provided there are no 'meter' problems.
I'm still concerned that you have 'regular' newer nickels that ID as 'foil' ,,, 'nickel' ,,, and some ID as 'round tab'. The nickel 'span' on a CZ is hardly ever that wide. Silver nickels from WWII will do this.......... but certainly not the newer nickels in your pockets. On the nickels that ID as 'foil'...and the ones that ID as 'round tab'.........,,,,,,,,,,,,.......... can you see/tell any major difference between these nickels? Are some badly damaged....or the 'rim' of the nickel has a bad/deep cut?
..... I ask, because I have never witnessed this problem before. Now...... if you hold a nickel at a steep angle.... or on edge, , , sure, the unit can ID the nickel as 'foil' and/or 'round tab'. Also, at 'fringe' distances,,, the unit can also give these results.
Tom