LCD Questions

Hi i keep noticing something that i find irratating for some reason one side of my tv seems to be brighter, its noticable when the screen is dark in 720p mode. I tried lowering the backlight but its not making a difference. Also when i change setttings, i noticed that say if i change channel, then they go back to default settings and dont save. oO. Help please

Sorry for the really late reply, i have been off 4 a while. Its a Mirai 27 inch, and its got a decent picture but tends 2 play up quite a bit, and always reverts back to default settings. Maybe its because i got it fairly cheap, and that was like over 2 years ago