You said that performed these calibration prints at 2880, presumably on plain copier paper. I find that 2880 is too high to reveal what is going on, as it overloads the paper. I prefer 720 for diagnostic purposes, as any issues are clearer. It's not as smooth a print, but it reveals more IMHO.
Harry Lockwood's comment about micro-banding in the first and last inch applies to the smaller desktops like the R3000 and smaller (probably the P600 as well), but not to Pro printers like the 3800/3880 and larger. There's more info on my blog, but it doesn't apply in your case.
---In QuadtoneRIP@yahoogroups.com, <rdeloe1@...> wrote :
Is it possible that the LM channel, with its missing 3 nozzles, is affecting all the other ones? Even on a print made with QTR
and 8ink file in Calibration mode (which I thought was designed to isolate the channels from each other)?