Council officials are looking at calling in noise specialists in an attempt to locate a mystery hum disturbing residents of a Co Tyrone town.
People in Omagh have been reporting a persistent low level hum or buzz in the town for several weeks.
Noise officers have been sent out to investigate it and have heard it, but have so far been unable to identify the source.
Senior official at Fermanagh and Omagh council John Boyle told a recent meeting the issue would "not be an easy one to crack".
He said existing equipment was not sensitive enough to find the source and they would either have to buy new equipment or employ a specialist contractor.
Among the potential culprits being investigated are air-conditioning units or power lines.
The council has been in contact with the company responsible for electricity distribution.
The issue was first raised by Alliance councillor Stephen Donnelly. He said he has received multiple reports from a wide area of the town.
He said the noise had led to a "significant degree of discomfort" for residents.
He said he appreciated that it could be difficult to find the source given "the potential for multiple sources".
Mr Boyle told councillors that if the source could be identified the council had powers to issue enforcement notices.
But he said before that could happen the council would have to be very sure if had found the right location.
Low level noise disturbance like this has become a global phenomenon in recent decades. It has been reported all over the world and has become known simply as 'The Hum'.
Speaking on RTÉ's Morning Ireland, Mr Donnelly said people characterised it as being a persistent buzz or hum sometimes accompanied by a sense of vibration.
"For some people, it's something that they've gotten used to.
"For some people, they haven't heard it, but for a considerable number of people, it's something that's providing a disturbance that is giving real cause for concern."
It seems to happen at night time and mostly around 10pm until midnight, he added.
"It possibly is because of the fact that around that time traffic tends to be at its lowest point and it then becomes a bit more audible and tangible, but that seems to be the issue."
Mr Donnelly said he started receiving complaints about this in late October.
"We initially thought that it was limited to the southeast at the time.
"But as time went by and people started to engage with me, it became clear that it was something that was affecting the entirety of the town, and the possibility is that it is seasonal.
"It's possibly related to weather, but I think the honest point at this stage is that we don't know the actual origin and we have to be able to try and establish the facts first before we can secure a solution."
Additional specialist equipment will have to be used to further investigate the source of the noise, Mr Donnelly said.
"I requested that the council investigate the matter a number of weeks ago and following that investigation they've confirmed that there is a legitimate issue, particularly in the Coolnagard area of the terrain.
"From that point, they've not been able to identify the actual source or potential sources of the noise.
"But they have confirmed that it is there and from this point going forward, they're going to have to procure additional specialist equipment to be able to properly zone in and identify where the noise is coming from."
On suggestions that it could be a flying saucer, he said: "I appreciate that whenever a story like this is draped in mystery and intrigue, it can be quite fun to kind of entertain different theories.
"But the thing that I always say to people is, don't trust the conspiracy theories.
"What is a fun problem will undoubtedly have a very boring explanation in time. And I have no doubt that this will be the same."