cannot stop booklet from printing 2 pages per side of booklet (4 pages per side of paper)

please help. 

no matter what settings i choose my booklet prints the same way - it is on the correct size of paper and folded and stapled correctly, but insists on printing 4 pages per side of A4. each "page" of the finished A5 booklet therefore has 2 pages printed in the wrong orientation rather than 1 page in the correct orientation. this stays the same seemingly no matter what I change. 

using the same settings to print a document as a booklet from word works perfectly, the issue seems to be just with pdfs. 

If anyone can advise it would be much appreciated.