Another ez trak question

george, another question. Today, I finished a milling cut using the jog feature and selected the backslash to home the z axis. I turned the spindle off but could hear a back and forth noise. Putting my had on the z servo, I immediately noted that to be the source of the oscillation. I selected z to jog, moved the axis down a tad and the noise ceased. This is the mill where I replaced the Z drive and EMI said I did not have to tune the drive. Will tuning get rid of this problem? This is the same mill that had the skipped x axis moves.

I have not reloaded the software yet. Could this be another software problem? Thanks, Jim