No - no need to replace a board. Resit all your chips and see if the problem goes away.
Take off the conncetors one by one and resit.
Also when the game is on give the connectors a wiggle and see if the game resets itself. if it does then halleluyah! Youve found the faulty connector. problem with intermittent faults is that when its working OK - there is nothing to fix!
If you really wanted to - you could replace all connectors
