Some people are saying that it's because of a filter that she was using on the recording but it's hard for me to see how that would be the case.

Rumour is that JKKK Rowling was fairly normal and then she fell down the terf pipeline, shut herself off from all her friends and family, and spends all of her time online seething over the fact that trans people exist. So if that's the case I could imagine that something broke in her brain and that's how her house ended up this way.