On good days, it sounds like aeroplanes.
On bad days, it sounds like a wailing ghost.
To children, it sounds like howling wolves.
Since the middle of last year, the quaint South Korean village of Dagsanri, on the island of Ganghwado, has been blasted with an array of eerie and unsettling noises.
They come from large speakers positioned on North Korea's side of the demilitarised zone, just under two kilometres away.
"It shifts between sounds like car brakes, tearing noises, and metal grinding," local Kim Wan Shik said.
"Many people who hear the noise frequently are taking anti-anxiety medication. It's extremely irritating."
Ghosts, sirens and animal cries
For decades, arch rivals North and South Korea have deployed various efforts to disturb or frustrate the other side, ever since the 1953 ceasefire agreement that halted fighting in the Korean War.
Using loudspeakers to blast the other side with propaganda has been happening on and off since 1963, stopping in 2018 after a rare summit between each nation's leaders.
But tensions have escalated in recent years after Pyeongyang ramped up its intercontinental ballistic missile program, nuclear ambitions, and most recently, forged a new alliance with Russia.
For the past year, both sides have engaged in tit-for-tat annoyances.
The weird noises from North Korea are terrifying children and keeping people awake all night. (Reuters: Korean Central News Agency)
North Korea sent rubbish-filled balloons to the other side, angry at South Korea for failing to stop its residents from deploying propaganda-filled balloons.
In October, South Korea was accused of sending a drone to the North Korean capital Pyongyang, dropping propaganda leaflets, something the South Korean military has denied.
Meanwhile, in response to the filth-filled balloons, South Korea has been blasting K-Pop music across the border.
It was soon after this that the eerie North Korean noises started, playing anywhere between 10–24 hours a day.
The loudest sounds have often been heard in the middle of the night.
"Sometimes it sounds like a siren, sometimes like a ghost, sometimes like animal cries," village leader Ahn Hyo Chul said.
"Our grandchildren say it sounds like wolves from North Korea."
People in Ahn Hyo Chul's village are suffering from the relentless odd sounds from North Korea. (ABC News: James Oaten)
For residents, it's having a profound impact on their mental health.
"I couldn't sleep until 4am," local Kim Ok Soon said.
"I stayed up all night. It gives me headaches, and my grandchildren can't sleep because of this noise.
"They come down to my house for breakfast in the morning, saying 'grandmother, we couldn't sleep because it was too noisy last night, and now we have headaches'."
Tit-for-tat noise battles
Of the 8,200 residents in the region, just over half have reported the noises causing "distress".
South Korea has installed sound proofing windows on dozens of affected properties and offered earplugs to all residents in the area.
Some residents want to move homes but appreciate it would be impossible to sell their houses in the current climate.
There are also ongoing negotiations about financial compensation with the South Korean government, but residents aren't overly enthused by the amounts that have been discussed.
"What we want is simple — stop the broadcasts to North Korea. That's it," Mr Ahn said.
"They're broadcasting in response to our broadcasts, so if we stop, they might stop too."
Eerie noises block out K Pop
South Korea has taken a much more hawkish stance towards the North under the administration of conservative President Yoon Suk Yeol, who is now facing impeachment and criminal charges for imposing martial law in December.
Some in the administration don't want to look weak against the North and accept the pain of border residents as an acceptable price to pay.
The noises coming from North Korea help keep out K Pop music played by South Korea. (ABC News: James Oaten)
"Like all politics, it's about who pays the cost to whose benefits," said North Korean expert Bong Young-shik, from Yonsei University.
"These residents are the major victims of the hardline policy waged by South Korean government."
Dr Bong adds that the noises, while a clear irritation to some South residents, are also likely designed to block out the K Pop music, as it fears its own civilians or soldiers being lured by the glitzy South.
"What may look like from the outside crazy or irrational, makes perfect sense for North Korea leadership," he said.
"Maintaining regime stability and sealing its people from any influence from outside are essential for the stability and the survival of the leadership."
For now, the residents on the South hold on for hope as their sanity wears thin.
"It's so painful," Ms Kim said.
"I feel like I'm going crazy now. My head really hurts so much."