Hi there I been getting overhang on Booklets.
Like the staple don't happen in the exact centre and and one hald=f over hangs the other
Don't know if the photos are clear enough
The finisher folder is out of alignment
Log on to the C75 as admin and go to Machine Status > Tools > Common Service Settings > Maintenance > Finisher Adjustment > Adjust Fold Position
Then I guess you will need a technician then because the settings are certainly not optional, so if there is no setting on yours to do a booklet fold adjustment then a tech will be needed to entire wipe the device, load the firmware again to get the option and then follow through with the adjustments