Cut size on XCarve too far from design size in Easel

I have some projects that were done last year in Easel and cut with XCarve where the cut dimensions were within .005" of design. I have since upgraded to the latest Easel driver and now the same projects cut smaller by about -.015". Is there something I can do to bring back the accuracy?

I did an upgrade of the grbl/arduino firmware, followed by a check of the mm/step setting and a test to verify that the XCarve was moving exactly the distance that Easel was telling it to. Tightened the belts in the process. Also, I reset the current pots on the grbl. All this made no difference. The XCarve, after having been used for more than a year was still in great shape.

The inaccuracy was caused by a change in the default feed speed settings. I found that the inch/minute for HDPE was defaulting to 40, which the cutting tool was happy to cut at but was way faster than my previous setting of 15. After the speed change, the accuracy returned and now is within about .005" of design.

.125 single flute upcut