embedding audio file inside a grayscale image... i have some issues reguarding audio processing.?

i have some issues reguarding audio processing steps are: read and convert audio file in binary using these line of code ( conversion is due to domain as my image is in time domain so audio should be in time domain too )

sound = wavread('D:\MATLAB\audio files\funky.wav'); wavbinary = dec2bin( typecast( single(sound(:)), 'uint8'), 8 ) - '0';

after that i m applying AES algo to encrypt the converted audio file for enhancing the security as audio file is our secret file

AES demo file is attached here but it is giving errors at the end of execution errors are

Error using cipher (line 38) Plaintext has to be a vector (not a cell array) with 16 elements.

Error in aes_demo (line 37) ciphertext = cipher (x, w, s_box, poly_mat, 1);

after encryption i have applied DCT transform to compress the audio file the code for compression of audio file using dct is also attached here

lastly m using LSB for embedding on which i m working