Help!!! Has anyone ever heard of your ink cartriages disolving on the ends or possibly melting.This has happened twice to me now! Ive talked to a couple of roland techs and they say that they have never heard of such a thing! I have a roland sc500 print cut machine its about 8 yrs old.It has a heater on it but as far as i can tell its not the problem. Any help would be greatly appreciated!!