Canon Pixma 5750 Horizontal Lines?

The printer prints horizontal "bands" every 7,5 mm; corresponding with the movement of the paper after the printhead has moved once across the paper. The "band" is best seen on the dark parts of the print. From left to right over a with of 7,5 mm the colour starts dark and then gradually becomes lighter. At the end of the 7,5 mm the next dark part starts; etc. I have done all tests,(deep)cleaning and lining procedures and replaced cartridges. Is this an end-of-life situation or??