(CNN) The debate over a secret recording between Donald Trump and his longtime attorney Michael Cohen continued Wednesday, with both sides offering different explanations of what was heard on the tape.

CNN hired an audio forensics expert on Wednesday to review the tape and determine what is heard, what isn't heard and figure out what clues can be gleaned from the nearly three-minute clip.

In a recording from September 2016, Cohen mentions a plan to buy the rights to a story that Playboy model Karen McDougal allegedly had an affair with Trump years ago. The tape confirms that Trump knew about the payment discussion in real time, while his campaign had denied knowing anything about the topic.

Trump's legal team admits the conversation was about the possible payment, but says it was not illegal. No payment was ever made from Trump, Rudy Giuliani, the President's attorney, has said. Giuliani has previously acknowledged that the recorded discussion related to the buying the story rights.

Other parts of the recording, provided to CNN by Cohen's lawyer Lanny Davis, are less clear. One key question: What exactly did Trump say about "cash" when Cohen brought up the financing arrangement?

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