Try placing the ActiveX control as the last object in the cycle. Don't really know why this works, but it solved the problem we had. We have reported this issue as a bug in version 5.5. Hopefully in 6.2 it has been fixed.
Is the ActiveX control being defined in the Dynamics or Statics. I would strongly advise that ActiveX controls be defined in Statics only (like buttons and icons (with the exception of paging screens/list boxes))
Thanks for the suggestion to make it static. That seems to work.