The National Party says its campaign is not suffering because of the saga over the recording of leader John Key's cafe conversation.
Mr Key has laid a complaint with police saying his conversation with ACT candidate John Banks last Friday was illegally recorded by a cameraman.
The National leader is refusing to authorise the publication of the tape and has said the investigation is a good use of police time.
The police on Friday said they had warrants for four media outlets, including Radio New Zealand, regarding unpublished material and other information relating to the recording.
APN, TV3 and Television New Zealand have all confirmed they have also received the letter.
Radio New Zealand's Head of News, Don Rood, says the broadcaster will be talking to the police and consulting its lawyers.
He says the organisation does not have the original tape at the centre of the complaint.
In Queenstown on Friday, Mr Key said support for National remains virtually unchanged with the party averaging 51% in three polls released on Thursday and Friday.
"And what I think that shows you is that the New Zealand public are really interested in the issues that matter, they're actually not terribly excited by the sideshows that are created as part of a media campaign."
National's campaign chairman Steven Joyce is happy with the way the party has handled the issue of the tea tape.
"The Prime Minister has taken a principled stance on it and we're all very happy with it and our focus is on the election which is now just over a week away," he says.
Mr Joyce told Morning Report the party's internal polls show the public does not believe the controversy is worthy of further attention.
He says the party's polling shows 81% of people think there are more important issues to focus on.
Mr Joyce says some people in the media need to do some self-assessment over the weekend and decide what they should be talking about next week ahead of the election.
Meanwhile, United Future leader Peter Dunne says a quarter of the campaign has been wasted by media obsessed about what two men did or did not say over a cup of tea.
His comments have been echoed by the Green Party, while the Labour Party leader Phil Goff also says New Zealanders want to hear about the issues that actually matter.
Mr Joyce on Friday defended the comparison made by John Key between the recording of the conversation to British tabloid newspaper practices.
He said Mr Key was pointing out secret taping of politicians was permitted it could then be justified for other prominent New Zealanders, and then for ordinary people in difficult situations.
"And frankly, that's what did occur in the UK," he told Morning Report.
Mr Key has been criticised for linking the secret recording to the potential secret recording of parents concerned about a child being suicidal.
On Thursday he refused to say whether he would apologise to families affected by suicide who had been upset by the remark, instead saying he had established a working group to look into youth suicide.
Court hearing set
A date has been set for a High Court hearing for the cameraman who recorded the discussion, Bradley Ambrose, who is seeking a judgement on whether the conversation was private.
Lawyer Davey Salmon said a teleconference took place with a judge on Friday afternoon and the hearing has been scheduled for Tuesday morning at the High Court in Auckland.
Mr Salmon says John Key, the Attorney-General, TV3 and the Herald on Sunday were also represented on the phone call.
Banks not discussing tape
ACT's Epsom candidate John Banks has repeated his refusal to discuss what was said during the cafe conversation.
Following a candidates' meeting in Epsom on Thursday, he said it would be inappropriate to discuss the matter, with recording being the subject of a police investigation and court action.
New Zealand First leader Winston Peters has claimed that in the recorded conversation Mr Banks described the leader of his ACT Party, Don Brash, as a "strange fellow".
During the electorate meeting on Thursday Mr Banks publicly praised Dr Brash.
Don Brash says no doubt a casual remark may have been made about his leadership over the cup of tea, but a mountain is being made out of a molehill.