cant save my radio settings ..help

:banghead: hi everyone need some help guys.i got a double din stereo system dvd player and monitor for my vauxhall astra 03 plate. the problem im getting is when i set my radio stations and tone base loud settings there ok till i take of my face plate then they all go to default .can anyone help plz its doing my head in.thanks jamie:uhoh:

p.s bought from hong kong
tis is it
http://cgi.ebay.co.uk/In-dash-7-LCD-TV-Radio-DVD-CD-VCD-Player-USB-SD-MMC_W0QQitemZ110160334225QQihZ001QQcategoryZ67772Q QtcZphotoQQcmdZViewItem

the wire that should be connected to constant 12V is connected to switched 12V.