Denford 2600 router Mach3 conversion

Hi, hope someone can help. I am at the point of setting motor tuning in Mach 3. The router is using the original motors on both x and y axis. Both motors are two pole 4 cable jobs. I have set the drivers to 1600 micro steps. However when I get the motor to move the correct distance in Mach 3 it does not sound very happy. It sort of makes a hard to move sound. This is the same on the y axis. The z is a none original motor. I can,t find any information on the motors and both are positioned in very hard to get at places in the cabinet and more then likely will not have any information on them. I am sure this is a micro stepping problem but not to sure how to correct it bar resetting the drivers blind and hoping for the best. Before I start taking it all apart again. Can anyone just confirm or not that it could be the driver microstep set wrong. Both motors are getting enough power. Thanks