[App_rpt-users] Is there a "Be Quiet" command?

I setup a script to re-transmit the ARRL Audio news on the club Allstar Node. Here is my question, is there a way to kill playback of a file, in case there is emergancy traffic during the news? I tried the Parrot Kill command with no effect. http://ki6psp.blogspot.com/2010/09/arrl-news-on-allstar-node.html -- KI6PSP (Ed)