Printing in US Letter size instead of A4 - Printer error

[EnDorTales]

When I print, I always get the printer output set back to "Letter" size. Correct size would be A4. Then the print job stops with an error code, and I need to unlock the printer manually by erasing the print job.

Setup:

Ghostscript Version 10.03.0-3 installed through Snap on a Raspberry Pi4B/4GB, running RaspianOS Bookworm. All updated.
CUPS 2.4.2 installed on the Raspi.
Dell 1355cnw printer as network printer installed

Printer settings in CUPS:
Beschreibung: Dell_MuFu
Ort: HomeOffice
Treiber: Dell 1355 Foomatic/foo2hbpl2 (recommended), driverless, cups-filters 1.28.17 (farbig, 2-seitiges Drucken)
Verbindung: implicitclass://Dell_MuFu/
Standardeinstellungen: job-sheets=none, none media=iso_a4_210x297mm sides=one-sided

Printer settings in Ghostscript:
Medien: A4 ( Plain ) Medien konfigurieren
Orientierung: Portrait Landscape Reverse Landscape Reverse Portrait Auto
Druckmodus: Automatisch Farbe Monochrom
Druckqualität: Draft Normal High
Optimieren für:
Skalierung:
Druckauflösung: 300 dpi
printing-quality:
color-mode:
halftone-algorithm:
icm-color-profile:
n-up-orientation:
n-up-printing:

Printer Tray settings:
MPF Paper Type | Plain
MPF Paper Size | A4 (210 x 297 mm)
MPF Custom Size - Y | 297 millimeters
MPF Custom Size - X | 210 millimeters
Display Popup | On

This are the start settings. Whenever I print (paper size set to A4 in the print dialogue of the app), the printer claims it has "Letter" instead of A4 paper format.

Furthermore the Tray settings of the printer are set back to "Letter". The printer is not touched by anything, beside the print job being send to the printer.

This happens no matter if printing through AirPrint from an iPhone, or by Ethernet from a Mac (both on the current OS versions). But it already happens when I send a test page from the Ghostscript web server site.

In addition the margins of the page are set to zero: It starts printing right on top of the page, and has no left margin.

I have no idea why the settings are changed to US Letter size by itself - I am located in Germany and never use US letter.

Picture of Test page

[Arkanoid1973]

Hello,
I feel less alone :) I have exactly the same problem but with a completely different PC and printer...
When I print, I always get the printer output set back to "Letter" size. Correct size would be A4. Then the print job stops with an error code (024-298 for me with the xerox), and I need to unlock the printer manually by erasing the print job.

Setup:
Ghostscript Version 10.03.0-3 installed through Snap on a Sony-Vaio VPC-YB3V1E, running Debian 12.5 Bookworm. All updated
CUPS 2.4.9 installed on the Debian.
Xerox WorkCentre 6015NI printer as network printer installed

Settings in CUPS
Description : Xerox_WorkCentre_6015NI
Location : Salon
Driver : Xerox WorkCentre 6015 Foomatic/foo2hbpl2 (recommended), driverless, cups-filters 1.28.17 (color)
Connexion : implicitclass://Xerox_WorkCentre_6015NI/
Defaults : job-sheets=none, none media=iso_a4_210x297mm sides=one-sided

Printing options in CUPS
Media Size: A4
Media Source: Default
Media Type: Plain
Print Color Mode: Color
Print Quality: Normal
Print Optimization: Automatic
Print Scaling: Automatic

Printer Tray settings:
Paper Type | Plain
Paper Size | A4 (210 x 297 mm)

As EnDorTales :
Whenever I print (paper size set to A4 in the print dialogue of the app), the printer claims it has "Letter" instead of A4 paper format.
Furthermore the Tray settings of the printer are set back to "Letter". The printer is not touched by anything, beside the print job being send to the printer.
In addition the margins of the page are set to zero: It starts printing right on top of the page, and has no left margin.
I have no idea why the settings are changed to US Letter size by itself - I am located in France and never use US letter.
Below is the printed test page and the printer error code...

In addition
After searching in the files installed by snap, I was interested in the wrapper file corresponding to the driver I am using: /snap/ghostscript-printer-app/815 (or current)/usr/bin/foo2hbpl2-wrapper
In this file, all "default" media is set to "Letter".

I tried to modify this file to test but impossible to overwrite it because the snap folder is read-only...
I feel like it's somewhere around there... but this is getting too technical, I'm not a developer and I don't know what to do precisely... :/
Also note that the values ​​indicated in the media sizes menu have little to do with what I see in the "Tray" menu of my printer... Perhaps a correction should also be made on this point...

The right column numbers match what I found in the file "foomatic-db/opt/foo2hbpl2-PageSize.xml" that I looked at in the foo2zjs driver source code that I found here https ://github.com/mikerr/foo2zjs_

Thanks