Thanks for all the answers ..
Some strange goings on here.
Yes I provide profiles to my customers for different papers.
I have identified the issue a bit more:
I have received some images from a client:
They have assigned my profile to the image; when I view in CS4, it looks good, skin tones etc.
When I print in Qimage (using my profile (the same one as the customer has used)), the skin tones are all red, awful.
If I softproof in Qimage, it looks good, like viewing in CS4 as above.
So where are these red skin tones coming from?
I go back to CS4, I assign sRGB to the image - wow, very punchy, looks better than my profile - to be expected I guess as my profile is for printing.
Still no red skin.
I assign aRGB to the image, and bang, there it is, the red skin tones....
So it appears that my printer is printing using Adobe RGB (at least the colours look the same), even tho' the image has been assigned MY profile, and in Qimage I am printing using MY profile AND before anyone asks, I am printing using Application Managed Colors.
BTW, my paper is calibrated and I have tried re-profiled the printer using a 1728 patch target.
This is a Z3100.
Side note: If I get an image from a customer where they haven't assigned a profile, then it prints perfect.
EDIT: I just tried this print from CS4,
Image has MY profile assigned - normal skin tones
Printed from CS4 using MY profile and Application Managed Colours
The resulting print has red skins tones, very similar to what AdobeRGB profiling looks like.
Why oh why?