So in Mach4 I continuously have this issue:
-  open the Jogging Screen
-  select incremental jog button
-  choose any option other than the first option (1.0000) So for example I select 0.0100
- hit the "Z-" button
- machine jogs 1.0000
- after this happens and scroll through the preset options a second time and choose 0.0100 it works fine.

This does not happen every time I open MACH4 but it's has happened on more than a handful of occasions.

I am running
Mach4 build V4.2.0.4612
Build 4612
ESS V277.1
Avid CNCpro4896
Avid preset profile in Mach4

Thanks!

This is a long standing bug within Mach4 (see the attached screen shot)