Re-Export of CS5 PDF....oops

[frailer]

While I was away, compadre had to Place CS5 PDF pages in Indy CS4, so he could tweak the page sizes for a roll-fold. He could have done this in XMF, in a different way, but that's off-topic. On one page which had transparency/colour, the reExport caused the colour to go very washed out. I haven't seen this job, just had it described to me after the event. Has anyone experienced any degradation when placing CS5 PDFs in CS4 for reExport? Sorry this is a bit vague....
Sounds to me as though the Placed PDF has kept an unwanted profile on Export. Should have been a straightforward Preserve Numbers, then > EuroscaleV2 Coated on Export... have a look at Export settings involved. I'll try and get the PDF from him tomorrow, and Export it myself. But any thoughts on possibilities welcome. he had to do it in XMF after all.

[Syphon]

I don't think you can come up with a answer without getting hold of the pdf. I know I would be asking for the pdf to see what's going on.