I don't know why some people get it and others, like me, never see it.
I have used Mach since the Mach2 days and have had a manual Bridgeport conversion, a CNC Bridgeport, Beaver NC5 mill, Computurn lathe, Conect lathe, Chiron VMC and a coil winder and I have never once had that problem.
Might be worthwhile making a new profile from scratch and seeing if that helps, or even deleting the macro folder and starting Mach up and it will create new macros for you.
Hood