Arduino to Scoreboard

I'm trying to connect my scoreboard to my arduino uno. The arduino is supposed to send a pulse(or whatever it was called) to the scoreboard each time a correct button is pressed. But when I connect it to the arduino, the scoreboard increments on itself without me doing anything. Here is the circuit I got from the internet. What I did is replace the 555 circuit and replaced a pin from the arduino to the pin 5 of the 74ls192 which is like the trigger pin of the scoreboard. I also tried connecting the scoreboard circuit to the arduino ground and yet, it still increments on its own. What could be the problem?

Please show us a image of your wiring and attach the sketch you uploaded to the UNO.