As I understand it, the audio was perfectly genuine. Their interpretation of it as containing a racial slur is what was bogus.
If we are talking about the same Zimmerman audio, the audio was genuine, but deliberately edited to make it look like Zimmerman brought up the fact that Martin was black.
Actual audio:
Zimmerman: This guy looks like he’s up to no good. Or he’s on drugs or something. It’s raining and he’s just walking around, looking about.
Dispatcher: OK, and this guy — is he black, white or Hispanic?
Zimmerman: He looks black.
What NBC aired. Notice that the Dispatcher's question has been cut out:
Zimmerman: This guy looks like he’s up to no good. He looks black.
“Their interpretation of it as containing a racial slur is what was bogus. “
I had nothing to do with it!