Audio Processing using BF537

Hi all,

   I am new to DSP,just started learning one month back.

I have been given the task of audio processing in BF537 .

1) Audio filter design(DNR-dynamic noise reduction)

2)VOX implementation

3)cahnnel filters of 12.5khz and 2 KHz....

4)Scrambler and Descrambler.

i am not understanding from where to start.

Please someone help me out, i need guidence.

I have deadline on july last week.