Reply to Button Malfunction

Hey there!

Just got my MF! Sadly, the 1st button on the 3rd row from the top doesnt work..! :/ Well, not the button itself, i've tried to replace it with another and nothing! What can it be? the connectors? theres also a few solder smudges over the board, hope its not that! Btw, the LED in that position still works (at the startup sequence only).

Please help! Thanks!