A former MediaWorks staffer logged into the company's network after he resigned and pulled its radio stations off air, a court has heard.
Craig Vause, 49, had worked for the company - which runs stations including Radio Live, The Edge, Mai and George FM - for 20 years.
He appeared in Auckland's Waitakere District Court this week for sentencing after pleading guilty to two charges of accessing a computer system without authority and one of damaging or interfering with a computer system.
The court heard he used his exclusive access to technical systems to create a backdoor portal to its radio platforms.
The company has nine radio formats on 190 frequencies across the country and has millions of listeners every week, its website says.
According to a summary of facts read to the court, shortly before resigning from the company in 2015, Vause created a remote access for himself to the radio infrastructure. A year later, on Queen's Birthday Weekend, he used that access to temporarily erase technical configurations and reboot its system.
The court heard a "number" of radio stations couldn't route traffic and went off air while it restarted.
Listeners heard silence, Judge Kevin Glubb said during sentencing on Thursday, and engineers brought in to investigate the issue on a public holiday weekend cost the company $27,831.
Vause initially denied the offending, telling investigators he didn't know why his personal computer would be linked to the network, or why MediaWorks suspected him.
No explanation was provided to the court for Vause's motivations and Vause was said to have told probation report writers he only admitted the charges because he couldn't afford to go to trial.
His lawyer Arlan Arman argued a conviction would hinder his ability to find more work in the radio industry. He applied for a discharge without conviction.
Arman told Judge Glubb a conviction would sound the "death knell" of Vause's career.
He had struggled to find further work and a conviction would make it "extraordinarily difficult" to find an employer willing to hire him, bringing an end to his 26-year career, Arman said.
The application was opposed by police prosecutor Renae West, who said the offending was premeditated, and the effects must have been considered by Vause who she called
"the author of his own making".
"It should be noted there was a significant amount of premeditation and a significant amount of time to consider what the likely result of this (would be). He had to have known a conviction of this kind was likely to end his career and he still chose to commit the offences," she said.
"This was serious offending with the potential for serious repercussions."
Describing Vause's offending as a serious "attack" on a public broadcaster, Judge Glubb said it struck at the heart of the operation.
"There was clear malicious intent here, designed to cause maximum impact," he said. "It was a deliberate attack on the integrity of secure computers to cause maximum disruption."
Vause had been a "highly respected and trusted" employee which allowed him to "exploit" MediaWorks' systems, Judge Glubb said.
"The fact of this conviction and the fact of the attack on the network is something an employer would want to know."
He rejected the discharge application and convicted him and sentenced him to 6 months' community detention, 100 hours' community work, and a year's supervision.
He declined to impose a home detention sentence to allow Vause to work, to repay $10,000 in reparations to MediaWorks.
A MediaWorks spokesperson declined to comment.
Vause also declined to comment following the sentencing.