Freeview says an outage to TV services overnight was due to Kordia network maintenance.
Thousands of homes are reporting issues with their televisions, after they blacked out just after midnight. The service returned early this morning.
Viewers were unable to receive any free-to-air channels carried by the service. It's understood the Auckland region was the only area affected.
According to the Freeview website 'essential maintenance' was being carried out, and viewers could expect services to resume at 5am.
Freeview said it is following up with Kordia about the short notice given for the outage.
Kordia has access to the Freeview website to post any outage notifications directly but only updated the site yesterday, Freeview said.
Auckland resident John Hawke had complained about the lack of notice.
"Freeview is ignorant for not telling us anything. I was watching television, and then all of a sudden I thought something was broken," Mr Hawke said.
You can watch all of TVNZ's channels live through the TVNZ OnDemand website here.