Reading USB Wrong?

[giuntasfw]

Our Machine seems to being reading the USB incorrectly or just completely shifting away from our center point when we find it. If I want it to run correctly, I have to take the USB out and turn the machine off, then find my center point again and run my USB file. It gives me an error code if I try and run another file right after the other one has finished, which requires me to remove the USB and power the machine off. I also notice that sometimes the bit path shifts from pass to pass. Any suggestion or help is highly appreciated, Thank you! 

[Bob]

When you say "center point" are you referring to the X, Y, or Z zero? Or all changing at once? It sounds like one or more stepper motors are losing steps. How big is the work area of your machine table? How big is the piece you're machining? How close to the edge of the table are you clamping your workpiece? Do you get any error messages prior to, or after starting a job? What does the error code say?
Have you contacted Axiom yet?
Bob

[giuntasfw]

My CNC table is 50"x70" and my work piece is 32"x21". Also, I am referring to all axis points, sometimes it may run an inch above the work on the Z axis, other times it will run an inch or so below on the x axis. It seems there is no real consistency between cuts. I have a frame screwed to the top of the table, so I can slide my wood sheets in and out, while keeping the same center point. After running a file, I receive an error 4 disk err, so I have checked and replaced the flash drive. I'm starting to think it is an internal error with the sd card. I have also seen an error code 10 for a frame error, but that has only appeared once.

[Bob]

I think it's time to contact Axiom directly: axiom 
You may need to scroll way down the the bottom of the linked page in order to get to the contact area.
They are excellent when answering questions. 
Bob