I have the same problem, hadn't figured it out yet. I have a 2006 PRT Alpha. My bit runs deeper into the freshly surfaced spoilboard the futher you go down the X axis.
I contributed it to a very worn thin spoilboard and we put a new spoilboard on there and does the same thing. Very aggravating when you have Vcarvings on an entire sheet of material, the carvings on the X0 end are perfect but the X96 end are really deep.
2006 PRTalpha 96x48
3hp SEV spindle
Vcarve Pro8
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