Do you have a tick/check in [Zoom to Fill] in the Image Settings panel?
Maybe your image is not exactly the same aspect ratio as your paper.
Edge to Edge print only works for 3 sides. there is always one side of white border.
I'm printing borderless with my Canon regularly.
Check the printer driver for some kind of 'overscan' setting.
I mean Ricoh Copier - Not Canon Inkjet. Not sure but Canon Copier might be same as Ricoh Copier.
I'm using Ricoh Aficio MP C5000 and it is true.
this below sentence from Ricoh Copier manual
If [Edge to Edge Print] under [System] in [Printer Features] is enabled, the margins on the left, right, and bottom edges in relation to the feed direction will become 0 mm.