[amsat-bb] Yaesu G-5500 Azimuth Rotator Fluctuation Problem

I have a Yaesu G-5500 EL/AZ Rotator and the EA4TX RCI-SE interface board. Presently, I am using Nova tracking and ARS interface software. The elevation rotator moves very smoothly and accurately as it should tracking designated satellites. However, the azimuth rotator fluctuates back and forth within ~2-3 degrees. The fluctuation is very visible on the tower. Has anyone experienced a similar problem with their rotator?

This is almost as if there is some type of interference between the rotator controller and the interface. Is there anything within the controller that might cause this problem?

Thank you.

Gary N0EZH Chesapeake VA