[Rachael]

you only need to put the co-ordinates of the player if you are changing them to create an ~offset~ sound effect. In that case you need to get their position, and use the co-ordinates. ( the offset is not in the same format as, say, holding objects)
eg

pawn Code:

PlayerPlaySound(playerid,1098,0.0,0.0,10.0); // will play the sound at 0,0,10 on the map

If you don't need to offset the sound, setting the co-ordinates to 0.0,0.0,0.0 will play the sound for the player to hear.

if you want to offset the sound

pawn Code:

new Float:px,Float:py,Float:pz;
GetPlayerPos(playerid,px,py,pz);
PlayPlayerSound(playerid,1098,px,py,pz+10); // will play the sound 10m above the player

This is explained in the wiki as such, but the example they give is incorrect