Is there a way to adjust the zero speed point on the dyn4 drive when running analog command speed servo?

I have 2 servos with brakes and 2 dyn4 drives, being controlled by a +/- 10vdc analog signal with encoder output back to the controller. With servo enabled (using ENA input to disable servo when not being used) and brake disengaged, with a measured 0.009 vdc on the analog input I get drift in one direction. Even if I pull the db25 I/O cable out of the servo drive I still get drift in one direction. I can see the the ballscrew turning slowly and the control is seeing the encoder counts as it shows the drift on the position display. I can not figure out what is causing it, or if there is a way to turn a pot to adjust the null offset to cancel this drift out.

If I'm in RS232 command servo stays put like it should. I have an email into to DMM but of course I wont hear anything till Monday sometime and am trying to get this machine going.