Frequently our suppliers are getting e-mailed the incorrect purchase order document.

Frequently our suppliers are getting e-mailed the incorrect purchase order document.  The only constant I have is that our buyer/planners are updating a PO, goes to requires reapproval status and then they approve and go through their normal process our supplier is getting the incorrect document template printed with our PO data.  Suggestions?  We have been thorugh the workflow, can't seem to reproduce the issue, it is not one supplier, it is not one buyer/planner it is not one same type of PO data change.  We do not see in the workflow where Oracle is doing this.  Thanks