NOEL Sutherland reacted aggressively when the neighbour from across the street asked him to turn down loud music coming from his property late at night.
He was found guilty of trespassing and causing fear to his neighbours and the case against him has been adjourned for the preparation of a probation report.
Sutherland (40), of Collins Avenue, Whitehall, had pleaded not guilty to the offence on September 27, 2012.
The prosecuting garda said he was called to the scene and spoke to the victim, who said he was having "difficulties" with the man across the road.
It was the early hours of the morning and the accused had been playing loud music, disturbing his and his heavily pregnant partner's sleep.
The gardai crossed the road and spoke to Sutherland, who gave an undertaking that he would stay in for the night and that there "would be no further issues".
The officers kept both houses under observation and around eight minutes later, Sutherland left his house and ran across the road, entering the victim's garden.
The gardai pulled up and arrested him, noting that there was a strong smell of alcohol from him and he was unsteady on his feet.
As he followed him to the middle of the street, the neighbour said the music had been too loud and he thought he could have a conversation with him about it.
After he returned inside, he saw Sutherland go several times into his front garden, looking through the window and front door.
"I said no, a neighbour, my girlfriend is pregnant, she can't sleep, can you lower down the music," the man told the court.
Sutherland said "Okay" and closed the door, but then walked back to him and aggressively started asking why he had bothered him.
The victim said in evidence he was woken up around 1am by a loud noise and noticed that the accused was playing music in his car. He went to ask him to turn it off, knocking on the car window a few times.
Sutherland opened the door and asked if the victim was a garda. Both he and his fiancee became afraid and he decided to call the gardai.
"My girlfriend was six months pregnant and we were both stressed," he said.
The judge adjourned the case to February 19 for a probation report.