I had the problem, only by printing pdf files with pdf creator 1.7.2.
E.G. : a MS-Word file in landscape was correctly printed, but the additionnal page (landscape, coming from a scanned pdf file), was always in portrait…Â
Even when alone printed, a pdf scanned file in landscape was printed in portrait…
I solved it by unsinstalling last version 1.7.2 and reinstalling version 1.6.2.
I had the same problem when I merge portrail and landscape documents. I solved using old Ghostscript (v8.50). Now documents are correctly oriented in final pdf.