Q: Problem using switch control to play music

We are trying to use switch control for a student to be able to independently play music.  I have it set up to use the screen as the switch.  We can get it to auto scan and she can select the music app.  She can then auto scan and select when it gets to play.  But then it plays the music just a second and then starts scanning again.  How do I stop it from scanning once she selects play?