Printing 4-on-1 instead of the requested 2-on-1 happens regardless of which of the two interfaces is used:
HP-OfficeJet-Pro-8130e-series HP-OfficeJet-Pro-8130e-series_xxxxxx where xxxxxx is the printer identifier, undisclosed here for privacy reasons. (Sending to the interface HP-HP-OfficeJet-Pro-8130e-series fails completely, first with “Kann Daten nicht zum Drucker senden.” (German for “Cannot send the data to printer”), and, when restarted, the printing is reported as successful by the OS, though nothing is printed in reality. Probably, this interface is intended as print-to-fax, but I never managed to actually get a fax sent this way.)
