For August software:
For old software:
You have set " Spooky2 central is always connected with Channel #3 ", and this is why amplitude 5V is blinking. There's a gate on Out 1 that results in the 0 / 5 v fluctuation you noticed 4 times a second (4 Hz Gate). And you need to right-click the channel button and select "No". It will solve the problem.