Greetings and thanks for any help. Just bought a used Roland SP300V with the Cyan, magenta and yellow showing test print patterns good but the black pattern having missing lines as well as lines not ligning up. Sign ink supplier says bad print head - nice guy but of course hes in the business of selling print heads. Could anyone tell me - when a print head is both missing lines AND lines are not aligned right - can that be cleaned out? Heard of Print Head Doctor cleaning system but cant understand how that would fix bad alignment. Thanks