Sound Out won't stop repeating

[Lisa Vittorio]

I'm trying to program a 40ms startle noise to play 9 times, with 18-25 seconds between noises. The participant won't need to enter any responses, and they will just be looking at a blank screen. I made a BlocProc with 9 samples, playing the noise and showing a blank screen. I can get the sound to play, but the problem is that it keeps repeating beyond the 9 trials. It's not set to loop, and I'm not sure how to make the experiment end after the 9 noises. I'm also not sure how to vary the time between 18-25 seconds. Does anyone know how to fix this? I've never used E-Prime before, so if you can help me in laymens terms that would be much appreciated!

Thanks in advance :)