Seamless Pattern - White lines appearing even when printed

[hkartte]

Basically looked through the forum as best I could and tried pretty much everything that anyone has said. Not sure if I missed something?

I'm having problems when placing vector patterns together -  I don't like to rasterize stuff generally.

I've attached three images: one is the PDF file of two of the same patterns. One is rotated and the other is not. I thought I was having the white line issue with only rotated patterns - however - in Affinity itself and in the PDF image (which I previewed in Chrome) the non-rotated pattern had no white lines, they may have come and gone when zooming in and out, but for the most part they weren't there. When I exported to PDF, they had gone. But when printed out, they were far worse than I anticipated. 

I'm not sure if this is me or whether Affinity doesn't like seamless patterns made with vectors. You get the white lines even if you place four square vector tiles together. 

If there is a private link where I can share my work then someone might be able to help. This is so important.

THANK YOU

Pattern test for print.pdf

[GarryP]

This seems very similar another thread which you started a couple of days ago: https://forum.affinity.serif.com/index.php?/topic/144616-white-lines-appear-when-rotating-seamless-pattern/
Are they different in some way?

[lacerto]

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