I have vertical banding with my MX922 looking like: https://community.usa.canon.com/t5/Desktop-Inkjet-Printers/Pixma-mx922-shadow-printing-even-after-auto--manual-align/m-p/336095#M12613

Canon tells me to clean the transparent band to correct both this problem, - as well as the BK lowest bar on the test page printing blue instead of black.

I opened up the printer as they show users to do and the transparent band was completely filthy! If the band is so sensitive and the effects so far-reaching, I am surprised it has been working fine for so long! anyway, I cleaned the dirt off with a tissue and rubbing alcohol and firstly, there is no difference to the banding at all, if anything it is worse? But secondly, the BK band is no longer blue, - it is now completely gone??

I'll bet I got 95% of the dirt off the front of that band. Is completely cleaning that band for a few hours the solution here or is it a wild goose chase? I do see on that Canon community support page Canon likes to tell people to clean the band prior to telling them to buy a new printer. to solve this problem.

I have already been told to buy a new printer with this MX922, prior to discovering that the whole problem causing the YOUR PRINTER HAS DIED error message lay with a small piece of paper lodged in the paper path somewhere. So I cant help but think that possibly Canon might conceivably have some ulterior motive for telling me to buy a new printer?

I see there is quite a thread of discussions on this exact problem at the link I gave with the general consensus being that it is an inherent problem with the electronics of the cartridge. If that is the case, surely the problem should exist with most or all MX922 printers as well as every other printer that uses this cart? And Canon wouldnt need to deny all knowledge of it? They's just correct the problem with all new carts??

Then someone offers the suggestion to flush the cartridge! whatever that means, If that was the solution, wouldn't changing the cartridge cure it every time?