trying to remove...sort of a purr? feedback or reverb?

I’m editing an audio track of a woman speaking. I’m not sure if it is reverb or other feedback of some kind (I am inexperienced!), but there is bit of muddiness or a kind of purring sound with her voice at points that I’d like to make less noticeable. It’s only when she speaks, so Noise Reduction doesn’t really help, and I’m having a hard time isolating it in EQ. I’ve had a bit of luck using the free version of Couture as an expander via another recommendation, but the purring is still there.

I would love to learn how to fix it, and I’m curious too about what a more educated diagnosis of the problem would be. What is this kind of problem called, and is it an issue with the speaker’s mic being too close or did it happen through Zoom (where the audio was recorded)? Or something else?

I’ve attached a short clip. I’ll be very grateful for any help!

Mains-hum is the culprit. There is a plugin to reduce it
Then apply desibilator
suggested settings _.png

This is really great-- makes the sound so much better. Thanks so much! Desibilator also seems like it might work better than the other de-esser I’ve been using. All very useful, thanks for your help!

I forgot to include a link to instructions for the ‘hum remover’ plugin …
https ://