About sounds

I've create an application with sounds but I don't know how to stop the sounds.My application is something like this:
Start of Frame
-Deactivate Group 2

Group 1
-Run this event once - Play sample "music1.ogg" 0 times
Group 2
-Run this event once - Play sample "music2.ogg" 0 times

Upon pressing Up Arrow - Deactivate Group 1 - Activate Group 2
Upon pressing Down Arrow - Deactivate Group 2 - Activate Group 1

I think the error is with this line "Run this event once" but don't know what to put...

What can I do ? Thanks !

Closing a group does not stop the sounds inside the groups. To stop a looping sound, you must use "stop sample" or "stop channel".

you'd also want to replace the "run this even once" with a "run this even once when action loops", plus what nifflas said.

At Limit conditions appear only "Run this even once" and "Only one action when event loops". Where is "run this even once when action loops" ?

He meant the one that say: "Only one action when event loops"

Still, I can't see any reason why to put those "play sample" actions in groups, what are you trying to accomplish with that? Closing a group does not revert the actions within it, you can't stop a playing sound by closing a group.

Why not just:
Upon pressing Up Arrow: Play sample "music1.ogg" on channel 1, 0 times
Upon pressing Down Arrow: Play sample "music2.ogg" on channel 1, 0 times

That way, the first song will interupt when you start the next, since you're playing it on the same channel.

I use deactivate/active Groups because I have put some sounds in there. Anyway it's working :D Thank you very much !