Lines missing after printing a drawing made to PDF

I am not sure if this a new thing or if I have just noticed but I create drawings and export them to a PDF set.  However I have noticed that when the PDF is printed dashed lines seem not to print.  I have checked to make sure that I did not have any non-printable lines (though if I did they should never had made it to the PDF).  I have also checked to see if it is doing it with different printers, which it is and with different clients.  I would believe it to be a Adobe issue and I am contacting them but wondered if anyone in the forum has seen this trouble?  

Tom-

I switched to Foxit for generating PDF's years ago and never looked back. Cleaner, easier, and cheaper.

Send me your problem drawing and I will print using Foxit and I will let you know if there are any issues.