Epson dx4400 heads won't align

I have an Epson dx4400 and some time ago the heads went out of alignment. I have spent at least three hours using the nozzle clean and head alignment functions but it's still no better, is there a factory reset I can try? It's the h alignment that's the problem, there's always a white gap on black and overlap on the other colours. All that trying to re-align does is to swap the position of the gaps/overlaps in the 7 test strips that print. I've done a google seach but all that does is bring up a load of red-flagged sites that want my credit card details. Thanks for any advice.

nb, I've had to put this as a 4200 all in one as fixya refuses to believe that there's such a thing as a 4400....