Are you sure <pixelratio> belongs to advancedsettings.xml? I can't find that parameter at the docs.
The Kodi doc says about video calibration:
Note: Always adjust the TV display settings first. Most issues are due to overscan and similar settings being enabled on the TV/monitor. Trying to adjust this setting in Kodi while these settings on the TV are enabled will have you running in circles and never being able to fix the issue.
So I think your issue is related to overscan settings. Read about overscan settings at config.txt (disable_overscan, overscan_scale etc.).