Pausing in Windows 7?

 I have a situation where a user has automated the process of printing several documents to pdfcreator through a MS Word vba utility.  He opens a file that is basically an index of files to be compiled together and starts the process.  The process sends the prints to pdfcreator in a wait/collect state and then after the process is completed it combines all the documents and continues the print to get one output file.  What we are seeing is that when the user is doing this in Windows XP the process works fine, but doing the same process in Windows 7 64 Bit after every 5-8 prints sent to the PDFCreator queue it pauses for 1-2 minutes before becoming responsive again and continuing the batch operation.  Is there a stream memory limit in Windows 7 that would be causing this, or is there some setting that may stop this pausing from occuring?  The documents getting printed are a mix of Word, Excel, and PDF files.