ABC chairman Justin Milne tried to stop triple j moving the Hottest 100 music countdown because he was afraid of what Malcolm Turnbull would say, sources have told Hack.

Around mid-2017, after extensive consultation and a massive listener survey, triple j privately briefed the ABC board on its decision to move the date of the Hottest 100 music countdown away from Australia Day to a nearby weekend.

It presented independent research showing a majority of listeners (60 per cent) were in favour of moving the Hottest 100 to a different date.

However, ABC board chairman Justin Milne did not support the idea, and placed direct pressure on triple j to back down.

According to sources, he named then prime minister Malcolm Turnbull's reaction as a key reason for why the station should not move the date.

When the announcement was finally made, on November 27, Communications Minister Mitch Fifield said he would be asking the ABC board to review the decision, but the prime minister's reaction was muted.

The Hottest 100 went ahead on January 27, and a record of number of votes were cast in the lead-up to the countdown (over 2.3 million).

Calls for chairman to resign

Mr Milne is facing calls to resign as ABC chairman following allegations he has failed to maintain the ABC's independence from government.

He reportedly sought to have chief economics correspondent Emma Alberici sacked following a backlash from the Coalition Government.

This morning, Fairfax Media reported that it had been given an email from May 8 in which Mr Milne told Michelle Guthrie, who was sacked as managing director on Monday, that the Coalition Government hates Alberici.

"I think it's simple. Get rid of her. We need to save the ABC - not Emma. There is no guarantee they [the Coalition] will lose the next election," he reportedly wrote.

Mr Milne did not comment on the accuracy of the Fairfax report in a statement released this morning, saying instead:

"The job of the ABC Board is to independently govern the Corporation, protect its best interests, ensure that it is well funded, well managed and that our content is of the highest standards. That is precisely what the Board has done and will continue to do. I do not propose to provide a running commentary on day to day issues which arise in pursuit of our duties."

At a meeting in Sydney this afternoon, hundreds of ABC staff unanimously passed a motion calling for Mr Milne to stand aside and for an independent inquiry to take place.

Communications Minister Mitch Fifield subsequently announced an inquiry "to establish the facts in relation to today's media reports surrounding the ABC."

Mr Milne says he intends to stay on as chairman.