Songs in different cultures use different sets of nonsense syllables, but there seems to be a strong consistancy about which syllables are used in any given culture. I always figured it had something to do with the "sound" of the language, but I don't know of any actual studies which have been done.

In some places drums and other instruments are taught using special syllables to represent specific tones, types of beat or ornaments (India, for one). Often nonsense syllables are onamatopoetic for the sounds that instruments would make.