I bought mine cheaply on Ebay some years ago and think it great, especially for printing on CDs.
However, the colour cartridges have recently started changing colours to black. I have no idea how this could possibly happen. Surely the black cartridge cannot leak into them? Has anyone got any clues? Cheers.
I have a Canon i865 printer and a couple of months ago I encountered problems with intermittent printing of black.
After a lot of Googling and searching this site I took the plunge - reckoning I had nothing to lose - and just washed out the printhead, many times in warm water until there was no visible staining - then dried it thoroughly.
It's now like new.
So, whilst it's not exactly the same problem, you could try it.
A new printhead costs virtually the same as a new printer.