I am running 2 axis lathe with Sanyo P5 BL 300w 100v servos with VSD-A Rev2 drives. I'm using the recommended motor amperage numbers I found on here.
My PS is a very large switching regulated power supply adjustable from 40 - 200v at 14A. I currently have it set to 160v. I know it is suggested to use a linear PS, but I already had this one and it seems to be a good fit for the requirements.

I have tuned the axis with GDTool and they perform quite well- very fast accel, stiffness, and good velocity, and no errors.

However, when I control with the Smoothstepper and Mach for S/D input, I got error #9 on the drives a lot when making rapid moves. I turned the tuning way down in Mach, even to 10x slower velocity and accel, and it helped a lot but I still get error #9 every once in a while, maybe once per part cycle. I know the servos can perform way beyond this in GDTool. Any ideas why I'm getting this error with the Mach/Smoothstepper control and never in GDTool?

Ps- I checked very closely and it is for sure #9 and not error #10.

Thanks!
-Colin