Please upgrade to QV11 IR which should be available at the download site by now.
As you understand the details are too vague to enable any kind of conclusion of the issue you have observed, so if you still have the same issue after that please provide a sample QVW to enable a evaluation of what the reason might be. Also please clarify what version you and your colleague are using during the comparisment.
When comparing make sure that you are using the same access right in case you have Section Access in the document, and also confirm that the document has not been reloaded during the comparisment.