Johannes ,
Did your problem happened after a software update?
I already experienced a similar issue but with an Epson 3800 printer. I can't remember exactly what triggered the issue [either a major Lightroom update or more probably a system update… really not sure about that] but using my print presets always produced offset prints. I had to go through every print preset, making sure that everything was OK (and choosing again every settings) and then update them. After that, my prints were centered.
Now, when I'm updating system software or Lightroom, I always print a few test sheets using presets. I use a cheap paper and only print a very thin (approx. 1 mm) black rectangle. This way, I waste a minimal amount of ink.
HTH