On A Mark Levinson 380 preamp, what does it mean on the display , code e 984 ?

When I plug in the  Mark Levinson 380 preamp , on the display , starts with 380, then reads code E 984,

What does the, " code e 984  "  stand for ?

Owner's manual for the 380S doesn't say anything about the error code.  I would send an e-mail to Mark Levinson and ask their service representative.  Or call the company.  They respond quickly to my inquiries.  Still can't get a schematic for the ML3 from them, but, oh well.

Thanks ,minorl and willcycle.