I have a funny problem with my box - when I switch on from the wall plug sometimes the OS will not boot up - I just get a green LCD.
Sometimes it will boot up straight away, sometimes I have to switch on and off a couple of times , sometimes I switch on/off about 20 times and it will boot up.

When it does boot I can flash etc OK. If I also put in standby from remote it is also OK.
What could this be?. I know basic electronics so could look inside. btw what screwdriver type do I need to open the side of case - they are like torx with a pin in the middle.
Thanks for any help
CE