a problem playing sound in matlab

Hello guys, i'm doing a programm in matlab, where their is a ball bouncing and two sounds, and each time the ball bounce, their is a sound that is played, one of this sound should be played on one of the bounce randomly, for 2 two first bounce i have my sounds that are working but the two others, in one of the bounce their is no sound, i made a brake point for the 2 last one and the sound works work, so i did a stop (0.001) but it didn't works so i tried stop (1) and it's work but also my bouncing stop for 1 sec so i need to know if their is any sollution for this problem without using the stop.

Thanks.