Hi,
So you still get a milky white skimmer column? IF so, not sure what the problem could be, unless you cleaned it so well that it's going through a break in stage again, but that should only take couple of days.
I think i would go to proteinskimmer.com and see if you can download there cleaning PDF and see if you can get the spray injector cleaned out, maybe that could be the problem.
Something else you might try is pumping air into the air intake. We have an EV400 and it didn't want to push the water up the column as high as we wanted, so we added a strong air pump and let us adjust it much nicer and now it really cranks out the protein.