using beta NTF NMF with audio signals, source separation code

Hi,

using this code: http://fr.mathworks.com/matlabcentral/fileexchange/38109-simple-to-use-nmf-ntf-with-beta-divergence

if K is 20, how do I save the 20 separated components to wav files? Also, I am not exactly sure how to USE this code with an audio mixture. any help would be appreciated. Thanks!

John