I was having a similar problem. It was because the settings on my 7610 were not matching the settings from Illustrator.
When you open your print box from Illustrator, or whatever app, choose printer preferences in bottom corner. This will open your 7610 printer.
My printer was set for 8*10 instead of 8*11, so I had to reset the paper size. Maybe your printer is stuck on a half sheet setting. I also have to exit the 7610 dialog box but then immediately go back into it via the print preferences and just hit ok (otherwise the print dialog box doesn't adjust for some reason). Somehow my Illustrator does not override my 7610 settings so I have to do this for every settings change.
I hope that helps.