Ok, I did as suggested but found no sign of anything obvious at all so I decided to take it all apart to get to the bottom of the main board just in case there was anything there. There wasn't. So then I decided to use an air blower on the switch and the whole player. I also gave the switch some good strong taps to hopefully clear anything that might be causing the problem. I also cleaned the ribbon ends with rubbing alcohol. I then put everything back together fully expecting it not to have worked. I am pleased to say however, that it did work or something did anyway. So as long as the issue doesn't return, its problem solved
Thanks for the advice latreche34, much appreciated