Very stange, but it helps! (Sample Programs)
Sometimes the ball moves very slow, stops when hitting the paddle and an error message appears. But it helps when I place something like 'wavplay "hit.wav"' at the start of the program:
# paddleball game made with sprites
# sounds from
print "paddleball game"
Even more strange, when I comment it out
# wavplay "hit.wav"
it still works!!!???