Well, there is a possibility -- Infra-red keyboards do emit the same light as a TV's remote does and it can interfere with the remote's transmissions. Is that what you have? Wireless keyboard with your laptop??
Another thing to check -- Laptops do have Flourescent backlights as do LCD TV sets -- I have seen backlighting like that literally STOP the remote signal getting to the TV.
Simple test -- if you have those in your TV room and your TV starts misbehaving -- get the Keyboard into another room to see if the problem stops. With the laptop, simply close the lid and see if it stops. Last ditch scenario would be hiding the wireless mouse, but that's unlikely in my opinion.
I've not seen it myself, but one of the major manufacturers had problems with their own TV backlight flooding the reciever in the TV set and the TV would turn on, and do nothing else afterwards. They built a filter to fix that problem.
Now the side button controls can be affected too if there is a strong source of Infra-red lighting in your room, so look at anything that is wireless, anything that has a remote, anything that has flourescent lamps in it, and attempt to either turn it off when your TV misbehaves, or cover it/conceal it or remove it from your TV room to see if the problem disappears
The last resort is to replace that board, but....you want to verify the IR reciever is the source? Simply take some black tape and cover the reciever on the TV set. Block the TV's IR reciever and see if suddenly your side control buttons start working again.
However there is one more test too...You left your TV on overnight, right? Maybe your TV works fine when it's hot, and doesn't when it's cold. If you find your TV misbehaves only when you turn it on first thing, then you have to see if the problem occurs when it's cold.
Run those tests, and get back with me on the results, ok?