Hi,
when I first started with Mach3, before I had Home switches I used to set 0,0 at roughly the centre of the table.
I noted that whenever Mach crossed the positive to negative boundary it would hiccup ever so slightly, not enough to
lose steps, more of an audio thing. While I never proved it I was of the opinion that as the machine co-ords passed thru
zero the PC had to do extra work to avoid a divide-by-zero type numeric fault.
In more recent time my machine homes to an extreme corner and so my machine never passes though machine co-ord
of zero...unless I'm on my way to a crash!. The little audio hiccup disappeared and has never come back.
Craig