Sony Kf-42sx300k Brightness Prob

Have a SONY KF-42SX300K, when the brightness is turned below 48 all back images turn to RED? turn it back up to 48 and the pic goes normall again.

I have been in to the service menu, and had a bit of a look around, the only thing i have noticed is that the colour, contrast ect have 2 figures next to them which are set to the same, but the brightness has 2 figures which are set to different numbers, not sure if this has anything to do with the problem? as someone may have messed with the tv.

BTW The tv has no guarantee as it was given to me like this. A friend has the same Tv so i might ask him to check the settings i mentioned above to see if they are correct like this.

Any help would be appreciated