This is my response to you:
1. You must know that if the rumour if proved to be true does not amount to defamation;
2. Therefore if this rumour is false then you civil as well as criminal remedy;
3. Take the audio recording and burn it into CD and go the police station;
4. File a police complaint against those people who have been spreading these rumours;
5. Also approach the civil court file a defamation case and claim compensation from the other side;
6. The compensation will be on the basis of the loss of reputation and the mental torture faced by you;
7. Take steps immediately otherwise the period of limitation is running against you.