Hello Tm,
I searched your issue on our Support Page and found this article, but I feel like you have already tried it. If this doesn't help you may need to call Support 1-800-821-2797.
Hi,
The color printing of my C400 has recently started printing off, specfically on the blue is where it is most noticeable. See image. I've tried the automatic color registration which doesn't fix it but beyond that I don't know what I need to do. I haven't moved the printer.
Thanks