LlPlaySound

Caveats

If sound is missing from the prim's inventory and it is not a UUID or it is not a sound then an error is shouted on DEBUG_CHANNEL.
If sound is a UUID then there are no new asset permissions consequences for the object.
- The resulting object develops no new usage restrictions that might have occurred if the asset had been placed in the prims inventory.
A call to llPlaySound replaces any other sound (so that only one sound can be played at the same time from the same prim (script?)), except sounds started with the deprecated llSound which always plays sound files till the end.
Sound files must be 10 seconds or shorter.
If the object playing the sound is a HUD, the sound is only heard by the user the HUD is attached to.
- To play a sound inworld from a HUD use llTriggerSound.
If multiple sound emitters play the same exact sound within range of the viewer an echo effect can be produced.
It is impossible to play two (or more) sounds at the same time and have them start playing at exactly the same time ~ VWR-15663^[c]

default
 {
     state_entry()
     {
          llPlaySound("some_sound",1.0);
     }
 }

[A, C]

llSetSyncTime() - a function for synchronising client side effects

Signature
function void llPlaySound( string sound, float volume );

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• string	sound	–	a sound in the prim's inventory or UUID
• float	volume	–	between 0.0 (silent) and 1.0 (loud) (0.0 <= volume <= 1.0)