unbuffer

Hi everyone, I am doing PCA on simulink now. what I did is first buffer the input sound into a matix, e.g.,15*10, and then apply pca and reconstruct the processed matrix. everything works well by now. but when I try to unbuffer this processed 15*10 matrix into frame by fram, i.e., 15*1, but it doesn't work. the unbuffer still output 15*10. DO you have any idea about that?

Thank you!