the printer sucks up the black ink from the fat 220 cartridge, and leaves the slender 221 black ink cartridges alone. thus, i have several 221 cartridges sitting here (from color packs) and must continue to purchase the 220s. any insights?
re MX870: the 220 ink cartridge is used up before the 221. i have several extra 221 black cartidges from the "color pack" purchases, but have to keep buying the 220... something's wrong with this. what can i do?
