code for recording an audio signal and converting it into binary and then again converting it back to audio ...KINDLY HELP !!!!

I have to write a code for recording an audio signal and converting it into binary and then again converting it back to audio. there is noise in the audio signal which i got in the result , its not the same. what should i do to get the same audio as i recorded ...after converting it back from binary . i even normalised the values... i am new to matlab ... kindly help... i will be very grateful for this .

[Jan]

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