This is basically passive aggressive denial.
I have dealt with hearing loss in relatives. Both my grandmother and my MIL would turn off their hearing aid when that were annoyed, but would then blame others for not speaking up.
With my BH he selectively wears his hearing aid, so I have to look all the time to see how loudly I should speak. If I forget, I am "mumbling".
If you have ever watched the BBC sitcom "As Time Goes BY" with Judy Dench, there is an episode where SO Lionel has wax in his ears and becomes deaf.He accuses everyone of mumbling. I cannot get my BH to watch that series, but I would love him to watch that particular episode.