xtreme embedded cas problem

lezb

I have an xtreme pvr model DSC 911 HUZ that has died on me it has never been flashed with emu file .It has lost the embedded cam the menu shows cam not installed .If I insert MM cam in the slot the set sees the cam (in both slots ) problem is that I am unable to scan any channels on any sat although My other sets have no problems on the same setup.I have spent many a happy hour on line trying to find a solution to my problem reading different opinions as to what is needed required etc and frankly I am confussed. My stb as it stands boots up menu is available but it sees no channels FTA or otherwise.DO I need to re install the emmbedded cam (If yes how???? and with what kit IE cas2+addon. Ucas was dreamload to version 1.09 as I remember.Any and all help or advice appreciated.As I have said I know this is quite a common problem but I have been unable to find a difinitive answer.
Thanks in advance
lezb