The slip skid ball bounces left and right in level smooth flight in my 4500 EFIS + 3400 EMS in my Glasair Sportsman. I also have the AFS Autopilot and Automatic Pitch Trim installed and working fine. The slip skid ball moves back and forth about half the width of the ball every 1 to 2 seconds. I thought there might be some electrical interference like strobes but they are turned off. Any thoughts anyone?

Damon Smith.
NSW. Australia.