The only time I have ever seen this was when I had an alignment that changed my origin and then went back to the previous alignment. I cannot pinpoint what caused the disconnect though, because it doesn't seem to always happen.
If you are using XML files with Data Importer, I would suggest removing the part from DataPage and re-importing the files and CAD.
Silly me...they were not landing on the part because I was only sending the x and y co-ordinates to datapage...Once I included z everything worked properly....lol
