I'm not sure that this is a software issue (running Mach 3) but I have my suspicions the problem is at the computer end and not the router end...the zeros of first just X and Y and as of Friday Z too, have been reset to another position without any changes made at the user end. This reset has occurred in the middle of cutting and while the machine was off or not running. And we're not talking a few inches here, it's usually 11in+, .5in on the Z axis. Read another thread about glitchy behavior solved by a windows update, I will try that. Does this sound familiar to anyone? Any other suggestions? Thanks!