'It cost £2 and was only something I had picked up. I would have got him something better. But the Lynx set came back up again and the argument escalated from there.
'He was really angry with me. He was jumping about waving his arms.'
Ms Armstrong called police after her boyfriend punched a hole in the kitchen door.
Manson confirmed to the court that the row started after he heard about the Lynx set. He said he gave his girlfriend a cuddle and she 'pushed me away'.
Sheriff Janys Scott acquitted Manson of the first charge, assaulting Ms Armstrong; and the second, putting her in a state of fear and alarm.
He was found guilty of damaging the kitchen door at his girlfriend's property and asked to pay £100 (NZ$189.50) compensation.
Defence agent Mark Chamber said: 'My client has spent 30 days in custody since he was arrested in respect of this matter.
'That is equivalent to a two-month prison sentence.'
Sheriff Scott said: 'I find you not guilty on charges one and two but you will be convicted on charge three and you will pay £100 compensation in respect of that.'