It could be the button board or the main board. Get estimates and see if it's more cost effective to replace or fix.
I can't tell if the remote works or not. Try new batteries.
My SANSUI LED TV STY1232C Buttons not responding, I use it as my computer screen. It used to work perfectly, until I started to have problems like speakers stop working shortly after I turn the screen on, whenever I would turn the screen on, the sound would work for a short period of time, then other problems came along, like some of the buttons would not respond, both the TV buttons and the Remote Control Buttons, only the Power buttons on the RC and the TV would respond correctly. Now, the Power buttons can only be used to turn the screen on, then it would stop responding after a couple of seconds, and no other buttons would respond at all. Do you guys know how to fix this, or if I should get a new screen?