That’s why I thought a sound recorder could be a solution. But if you are saying there’s no way to prove the recordings haven’t been doctored, then it’s out.
That’s not what I said. I said it would be better to have an independent assessment. It sounds to me that we have one owner who makes a bit more noise than usual, and a neighbour who is unusually sensitive to it. In your shoes, I’d be saying you didn’t think it was you, but if the neighbour wanted to install sound monitoring devices, monitored by an independent assessor, you’d be okay with that. And suddenly the cost of monitoring is in their financial court, not yours.