It sounds like you have a mismatch between the PC's (DNC Precision's) port settings and the Yasnac's. DNC Precision is giving you "typical" settings, but it is possible that the settings on your machine are different. It is not so important what settings you use - just so long as the settings match between your PC's DNC program and the machine control.
I haven't used the MX1, so I don't know if it has a simple way of checking and changing the DNC parameters... If not, check your manual for the parameter bits to change to get the DNC settings to match.