The "eerie" sound of a nursery rhyme which was used as a burglar deterrent "terrified" an Ipswich woman for about a year.
The woman, from Bramford Road, heard the sound of "It's raining, it's pouring", but she had no idea where it was coming from.
She rang local council officers, who tracked the noise to the nearby Farthing Road Industrial Estate, as first reported by the Ipswich Star.
It has since been turned down.
For several months she would hear the rhyme, which would go away only to come again another day.
The woman, who did not wish to be named, said: "The first time I heard it it was the most terrifying thing ever, I went cold and felt sick, and thought 'what on earth was that?'"
On Monday at 23:15 BST the sound of "It's raining, it's pouring" stopped the woman from snoring, as it began to play "literally every two to three minutes".
She called Ipswich Borough Council to complain about the noise, which other residents had also reported.
A council officer who was sent to investigate found the noise coming from speakers at a unit on the estate.
The alarm was set up to deter trespassers and a spokesman said it had been very successful but they were unaware of the effect it had on residents.
He explained that the song had begun playing continuously due to an itsy-bitsy spider.
The arachnid had been found on a camera that was linked to the alarm, he said.
"Every time the spider went across the CCTV it set off the alarm".
"We apologise to everyone that has made us aware they were affected - the alarm's intention was never to have affected the residents," he added.
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The woman said that on Tuesday she stood by her window as they tested a lower alarm volume, and "couldn't hear it".
A spokesman for the council said: "This is unique in our experience - it was difficult to believe a nursery rhyme would be playing in the middle of the night.
"We did hear the nursery rhyme playing from an industrial premises and it sounded very eerie at that time of night."