Sound in a Block doesn't work

Hi everyone! I have to put sound in a Block (it has to work during the task). This is my script, but I don't understand what is wrong. The experiment doesn't start, it tell me "loading" but then it never start. 

options

fullscreen

loading text Caricamento

startbutton text Clicca qui

set $j time-since-start



bitmaps

fixpoint6

Istruzioni
a
b
c
d
e
f




sounds

Chopin  www.youtube.com/watch?v=9E6b3swbnWg



fonts

arial 32





table stimoli
a    1
b    1
c    1
d    2
e    2
f     2




task associazione
table stimoli
keys x m

show bitmap fixpoint6 
delay 200

clear -1 
delay 200

show bitmap @1 
readkey @2 3000

clear -1

delay 200

save BLOCKORDER TASKNAME BLOCKNAME @1 TABLEROW KEY STATUS RT




block MyBlock1
message Istruzioni space

sound Chopin 
tasklist

associazione  25

end

silence Chopin



Thanks in advance for your assistance,

Deborah