Printing in red from Adobe Acrobat PDF's
We seem to be seeing a bug in Adobe Acrobat 8.1.2 where printing a PDF from within Acrobat Reader prints out with red backgrounds on images with certain documents, it may be in conjuction with HP printers. But we've only seen 3 cases in various offices so it's hard to be certain of that at the moment.
There doesn't seem to be a fix that we've found at the moment, so we recommend as a temporary solution until it is fixed by Adobe is to either downgrade to an earlier version or to use an alternative PDF viewer.
I recommend the FoxIt PDF Reader as it is free, works well and is fast and solves this problem for the people who have come across it.