Unpacking print job settings not identifying printerName

In AX2009, I created a class where I pass packed PrintJobSettings from table.field   ProdParmStartup.SetupPrintPickList.

When I instantiate new printJobSettings in my class run method, a new printerName is set with my default printer. What I'm having trouble with is assigning the packed container from ProdParmStartup. What I've got:

public void run(PrintJobSettingsPacked          _pjsPacked)

PrintJobSettings    ps;

; 

ps = new PrintJobSettings(_pjsPacked); // debug shows contents of pjsPacked same as ProdParmStartup

info(ps.printerPrinterName);    //shows my default printer

// alternatively

ps.unpackPrintJobSettings(_pjsPacked);
info(ps.printerPrinterName());    //shows my default printer

So it looks like the unpackPrintJobSettings does not unpack. What am I missing?