TV behavior

[OliverHK]

Hi all,

I need an advise. Our TV fell down. After switching it on there are no problems with the screen. Full colors, no blackouts , or spots. But the TV has now the following behaviors:

1. It switches off sometimes after 10 seconds, 2 minutes or sometimes after 15 minutes. I cant direct switch it on again, have to wait a few seconds.
2. When browsing the menu with the remote, lets say I input my mail address to sign in, it reacts in the beginning properly, but then after a while starts lagging. Very slow reaction reaction to remote commands until it offs again.

Where could the problem be? The main board? I am living on the Philippines and I could get a mainboard here for around 50 bucks. TV is 5 years old.
Thank you.

Oliver