Do you have any open or non updated InCopy assignments in the document?
Sometimes yes, sometimes no. Sometimes articles are checked out, sometimes not. Sometimes the objects being moved are part of articles, sometimes not. I have found no direct correlation here.
Have you tried the same things with the K2 plugins disabled?
Did you upgrade the OS after installing ID or migrate ID to the new machines?
@Peter -- on the older machines, we upgraded the OS in place. On the new machines, they were fresh installs all. ID's were not migrated, only personal files were later transferred. Preferences and all else were entirely fresh.
As for the K4 plugins, we did not try, since the system is integral to the work they do. However, we're also working with the Vendor on that. They don't seem to think K4 is the culprit either. However, we're in the process of contacting other sites with similar setups, though apparently no one else is experiencing what we do.