I am thinking that you would need to set up a trigger zone with one of the sound scripts assigned to it.
See if you have this script in your scriptbank folder to assign to a trigger zone.
soundareazone.lua
function soundareazone_init(e)
end
function soundareazone_main(e)
if g_Entity[e]['plrinzone']==1 then
LoopSound(e,0);
else
StopSound(e,0)
end
end
Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz, 2400 Mhz, 4 Core(s), 4 Logical Processor(s), 8gb RAM, Nvidia gtx660, Windows 7 Pro 64bit, Screen resolution 1680 x 1050.