Links to the 29 recordings were posted on Twitter a few hours before US President Barack Obama took the stage in Philadelphia to address the party's national convention, a meeting that formally nominated Clinton as the Democratic candidate for the White House.
The confab was meant to be a show of unity, but instead has exposed the raw anger of Sanders supporters who feel disenfranchised by the primary process.
The WikiLeaks files seemed timed to embarrass the party and Clinton, although the audio recordings did not appear to contain any bombshell revelations.
They came after the anti-secrecy website on Friday leaked 19,000 emails from the accounts of several top Democratic party leaders.
At least two email messages suggested an insider effort to hobble Sanders' upstart campaign against Clinton -- including by seeking to present him as an atheist in deeply religious states.
The uproar following the leak forced party chief Debbie Wasserman Schultz to abruptly announce her resignation on the eve of the convention she was meant to preside over.
In one audio recording, the angry Clinton supporter said in her minute-long voice mail that she was "furious" about what she perceived as party support for Sanders and giving the self-described democratic socialist "too much influence."
"Bernie is the worst person in the world to even be running in the Democratic Party because he's not a Democrat," said the unidentified woman, who noted she was on a fixed income and had donated $300 to Clinton.
"Quit acquiescing to this person who likes to play the victim card and who also has been attacking Hillary, which gives Trump all his talking points. I will leave the Democratic Party if the Democratic Party continues to coddle Bernie Sanders," she said.
It was not known which party official the woman was trying to reach.
In another recording, a woman -- possibly the same person in the earlier call -- was upset the party was letting Sanders supporter Cornel West serve on the platform committee, calling him "trash."
The audio files also provided a small glimpse of the daily inner workings of the party, with a staffer from an ambassador's office calling to make sure her boss received an invitation to a St. Patrick's Day reception at the White House.
Former ambassador to Austria William Eacho left a message to get details on an invitation from Wasserman Schultz to attend a dinner with Obama.
It was not immediately clear if the audio recordings were part of the original cache of 19,000 emails and attachments released by WikiLeaks on Friday.
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