Kyocera ECOSYS M3540idn: every print job requires a manual touch for the tray selection

Brand, model of printer: Kyocera ECOSYS M3540idn
Setup: corporate network printer installed via printers share
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Workstations: Dell laptops and desktops
O/S: Windows 7 Professional and Windows 10
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Every time a print job is sent to the printer, one is prompted to select on the printer's physical control panel the tray to use:
- 'check [status/job cancel]'
- 'add the following paper in the multi purpose tray; press [paper selection] to select the other paper source;
paper selection; use MP tray; [hold]; [cancel]'
- 'paper selection': [1]; [A4];
[2]; [A4]; [plain]
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Printer preferences on the workstation are:
. 'source': 'auto source selection'
. 'media type': 'unspecified'
. 'destination': 'printer default'
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Actions taken:
- power cycled MFP machine
- removed printer from the workstation and re-added it
- added it on another workstation running Windows 7 Profesionnal
- same thing happens
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Thanks for your input.
Pierre