A judge has sanctioned Fox News after claims it withheld evidence in a $1.6bn (£1.3bn) defamation lawsuit.
Dominion Voting Systems' lawsuit argues Fox News damaged its reputation by airing election conspiracy theories.
Dominion said Fox News did not turn over certain recordings. Fox News says its lawyers produced the materials as soon as they learned of them.
The judge also complained that Rupert Murdoch's leadership role at Fox had not been made clear to the court.
The disputed recordings were taken by a producer, Abby Grossberg, who has sued Fox News in a separate lawsuit.
In the audio, Fox host Maria Bartiromo speaks to two lawyers who represented Mr Trump during his attempts to overturn the 2020 election: Sidney Powell and Rudy Giuliani, NBC News reported.
The recordings were made available only after the pre-trial period when both sides exchange information about the evidence that will be used.
Delaware Superior Court Judge Eric Davis grew frustrated with Fox after Dominion's lawyers played the recordings in court, according to NBC News.
Fox News spokeswoman Irena Briganti told the BBC in an email: "As counsel explained to the court, Fox produced the supplemental information from Ms Grossberg when we first learned it."
In light of the delayed evidence, Judge Davis said he would consider appointing an independent lawyer, known as a special master, to investigate Fox's legal team.
Judge Davis also expressed frustration at the network's lawyers on Tuesday for not revealing the full extent of Fox Corp Chairman Rupert Murdoch's role at Fox News.
Attorneys for Fox News had said Mr Murdoch holds no official role at the channel, and does not make day-to-day decisions. But Dominion's lawyers said Fox News only disclosed to them on Sunday that Mr Murdoch is an executive chairman of the network.
Ms Briganti said there was no deception: "Rupert Murdoch has been listed as executive chairman of Fox News in our SEC filings for several years and this filing was referenced by Dominion's own attorney during his deposition."
But during Tuesday's hearing Judge Davis admonished Fox's legal team.
"My problem is that it has been represented to me more than once that he is not an officer," he said.
Dominion's lawsuit argues that the conservative network sullied the electronic-voting company's reputation by airing falsehoods about the 2020 presidential vote being stolen from
Donald Trump.
Jury selection begins on Thursday.