buffer function error using input arguments

[y,Fs,nbits]=wavread('C:\Users\GOTHAMI\Desktop\piano.wav'); [R1,C1]=size(y); [zas]=buffer(y,nspf);

iam getting eError using ==> buffer Input must be a vector.

Error in ==> prj3 at 9 [zas]=buffer(y,nspf); rror like this