Button 5 Not working

Hi I’ve built and installed my console, and works lovely. Except I have a problem with button 5, where it occasionally works but then just gives up. I’ve checked the TX light and it doesn’t light when you press the button. I’ve also tried grounding the connection and the light doesn’t light up. I’ve also switch buttons around so wired button 6 to button 5 connection and still no light. Basically have managed to track it down to the board rather than an issue with the actual button or wiring.

First thing today it did work, and the TX light lit up, but after a short while it stopped unfortunately.

Any ideas.