I can't remember the 'Secret Handshake', but its something like Press the SW-R button and then press the HW-R button 5X...some shenanigans like that.
I think the manual has the steps (or check OLH)
Just know that the system with reset all of its settings and maybe wipe all the files, so make sure that you know the settings and have the files backed up...
Depending on the current FW, even FD'ing the unit may still boot it up requiring that you add a new PW, which is OK as you'll now know it. if you want to get rid of AUTH, you'll likely have to downgrade the FW to an Non-Auth required version and then step it back up...
