Pete,
I didn't see that you mentioned which paper you were using (sorry if I missed it somewhere in the thread).
If it's something other than Epson's papers for the printer, you might want to look very closely and see if it's really banding you're experiencing and not the dreaded "pizza wheel" problem that often occurs with some brands of paper. You can do a google search with the words "Epson pizza wheel" to get a description of the problem and potential solutions.
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