VE 2010 SSV series 1 Blaupunkt unit fault

[bluesguy]

I thought you guys may have come across this before. I have a holden 2010 series 1 SSV Ute with a Blaupunkt head unit. Problem is the on/off switch on the unit does not work (volume part does work).

Is there a button combination that will fix this or someway of getting into the engineering mode to correct it. or has the switch failed in the on position?
I can turn it off only by removing key and opening drivers door.
Any clues you may have would be appreciated, thanks