The recent arrival of shipping giant Maersk's Rio-class ships to Port Otago each week has led to a flurry of complaints from residents around the harbour, including Portobello, St Leonards and Harington Point.
They say they are being kept awake at night by a low, thumping noise from the ship's generators.
The port company has tried several measures to mitigate the issue, including berthing the vessels further up the wharf, but a more lasting solution has not been found.
Port Otago chief executive Kevin Winders said Maersk was investigating an engineering solution to the 63Hz sound problem and he expected to hear back from the company next week.
''We are still working and talking with Maersk to get a significant reduction and whether that is feasible with the engineering options they're exploring in Copenhagen,'' Mr Winders said.
At first, it seemed the problem was confined to Otago Harbour, which acted like a natural amphitheatre, but issues at other ports had since surfaced, he said.
Weather also had a major impact on how sound travelled. The recent warm and still nights seemed to amplify the sound and carry it further.
''Clearly, we're engaged with them [Maersk] ... but ultimately it's their ships and we're asking them to do something about it on behalf of the community and Port Otago.''
News of a fix would come as sweet relief to many harbour residents.
Andrew Perkins, of St Leonards, said, at its worst, the noise was similar to a helicopter hovering above the house all night.
He has lived in the area for two years. Until about two months ago, he had heard very little noise from the port or vessels in the harbour.
He has contacted the port, including Mr Winders, and has also lodged two noise complaints with the Dunedin City Council.
''When it actually affects people and their health in a very wide circumference, which draws in Ravensbourne and Portobello, I draw the line there.''
Across the harbour, in Broad Bay, Elke Mathewson said the noise travelled directly over the water and into her harbourside villa.
It was the first issue she had had with port noise in the five years she had lived there.
''It's really, really bothering. I'm quite devastated. We've had cruise ships honking ... but these container ships are just something else.''
Otago Peninsula Community Board chairman Paul Pope said he had received at least five complaints in the past fortnight from peninsula residents.
He had also written to Mr Winders and was waiting for more information.
''We've got to give the port the benefit of the doubt at this stage.
''They've got to work through some issues and processes at the moment and I'm going to let them take the lead on that.''
