My Printer has color banding but perfect nozzle check

I recently purchased this printer at auction ET-3700 (bad idea ?) and whilst the nozzle check is perfect when I print an A4 color page I get a color band for each color printed across the page right at the at the end of document

Block Image

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 1
crwdns2934285:0crwdne2934285:0