Alan Jones' breakfast radio show is under review after up to a hundred advertisers pulled their support following a string of controversial comments made by the broadcaster.
Macquarie Media chairman Russell Tate wrote to clients apologising for Mr Jones' most recent scandal, in which he suggested Prime Minister Scott Morrison "shove a sock" down New Zealand Prime Minister Jacinda Ardern's throat to stop her speaking out on climate change.
In the sections of the letter published by Nine newspapers, which owns Macquarie Media, Mr Tate said the incident "brought into sharp focus" the need for broadcasters to be respectful and reflect community standards.
"Through this incident, we have experienced the ability of offended groups to greatly amplify their complaints and to actively disrupt you, our clients and your staff, who have done no more than seek to engage with the audience which chooses to listen to us," Mr Tate wrote in the letter.
He also reminded clients the broadcaster had apologised. Jones made an on-air apology, and says he also contacted Ms Ardern directly.
"Of course, we have seen valued commercial partners withdraw from Alan's program, but the fact is we got it wrong in the first place and we must now do everything possible to ensure that doesn't happen again," Mr Tate said.
"To that end, we have already commenced, with Alan's encouragement and support, a full review of the 2GB/4BC Breakfast Show's content, presentation and controls with a specific focus on audience and guest/third party engagement. That review will extend into all 2GB/4BC programs."
Jones' Ardern comments triggered a boycott, championed by social media activist groups Sleeping Giants Oz and Mad F***ing Witches, in which businesses including Koala Mattresses, Anytime Fitness and Volkswagen withdrew advertising from the show.
Mr Tate publicly warned Jones in August that if he slipped up again, his contract would be terminated.