Adobe Professional keeps resetting print preferences

Hi Community,

Over the last month or so my Adobe Professional print keeps resetting the print preferences back to default. This can happen many times a day, even in the middle of printing.

Specifically the defaut page size, which I set to A4 (based in Australia).

I can print one or two files to PDF, then next minute the thrid job has printed to Letter. 

Is anyone else experiencing this and found a fix?

Our IT department cannot find a fix.