Dead, but sometimes starts up and works for a second on two

Hi,

I have an IO (not sure which model but has the LCD display) which stopped working completely. Sometimes you press the button and it starts up, you see the intro animation for a second or two and then dies again, usualy doesn't do anything for a few hours after that when you press the button again.

I took it apart and the battery seems fine (3.8V), the button itself is also working. I wonder if this is a known fault and if it's realistic to try and fix it, or if it's going to be one of these microcontrollers or just any one of the tiny countless unlabelled resistors/capacitors and I'm better off just throwing it in the bin.

Thanks