Printing B&W problem

I have tried both Matt

Wow! You're a hard man to help, Pete
(A bit more detail in your reply would go a looooooong way to helping you out, just as if I asked a policeman for help and just said "I have a problem" - doesn't make his job easier does it?)

If they behaved exactly the same then there's not much else to do - the "greyscale" option on the printer driver should remove any colour casts as far as the printer can.

The only other thing I'm not sure that's been asked is what paper are you using? Profiles are printer + ink + paper dependent
(So it's quite likely you'll get a slight colour shift when not using the paper the printer's profile was made for.)

Matt