Gentlemen

I am using a C10 BOB with Keling KL4030 Drivers and KL23H286-20-8B motors for a Solsylva router.  I tested my system on the bench under Mach3 and was able to get everything working as planned.  Since disassembling and re-assembling in the machine, I now have developed considerable vibration/grinding sound type feedback coming from the X-axis motor.  I removed the motor from the machine and jogged X+ and X- direction.  The vibration/grind is severe, and the shaft appears to be reversing direction intermittently.  I have a similar problem with the Z axis motor when rapid jogging wherein the shaft locks, but the motors sounds as if it is running.  I am losing steps and position is all over the map.   The Y axis appears to run correctly.

I believe my configuration settings in Mach3 for tuning are correct.  Any ideas what my be the issue? 

Thanks

start by making a slowwwww short move and measure the distance traveled to the distance commanded. If that is accurate, what is the jog speed that you are trying to achieve when you hear the noise?

What does it feel like when you turn the drive by hand?