Digital BW, The Print

Hi, Does anyone have an answer to obtaining neutral tone B+W images
when printing as a CMYK file. I'm a photographer in the UK putting
together a 62 page photobook for a client who wants the book in B+W,
the company which produce the books for me need  pdf files created in
photoshop coverted to CMYK as they print on a commercial printing press,
I've just had the books back and many of the pages have printed with
slightly differing hues, mainly yellow, some blue. Having read many
posts it would seem it is very hard to obtain neutral tones due to the
difficulty of mixing the CMY inks to produce neutral B+W, however I'm
hoping there is an answer out there somewhere! David
www.blinkweddings.co.uk