TS9551c - thick ink lines on prints

[DearMother]

Hi, I bought my TS9551c in January. In February I noticed on some prints, that there was deeper ink in a band in the middle of the A4 piece of cardstock (300 or 350gms)

Now that band is on all my prints.

I've given the cartridges a deep clean, aligned the print heads and done a nozzle check. I only use canon inks. 

I have no idea how to rectify this and I'm hoping you can help. 

[Patrick]

Hi DearMother,

Please contact one of Canon's Technical Support Representatives via phone or chat. To contact a Technical Support Representative, please use the link below:

https://mycanon.usa.canon.com