AXYZ router cutting error

I uploaded a picture to show what I am experiencing.
When my CNC is cutting, it will shudder a little bit (most times, not all), and all of a sudden it's out of alignment. It is cutting .5" to the left of where it should be. This is happening in the X and the Y direction.
I have already contacted AXYZ tech support, but tech support told us we are running too fast (@75IPM). They recommended slowing it down. That doesn’t seem to make sense.
Help!
Thanks,
Jon