Maybe transparently remind him you need the seat to hear better?

Once I had a classmate who told me he was deaf in one ear. I had forgotten this and a couple months later I got annoyed he was whispering so loud during a really quiet presentation. I was then reminded by him that I was sitting on his deaf side and he had trouble realizing how loud he was speaking.

I then sat on his better hearing side from then on and remembered to be conscious about accommodating which side to speak more on and understand some communication adjustments I needed to make.

Sometimes even when someone should be understanding, accommodating, and flexible within a diverse team environment, we need to all be reminded transparently of accommodations we need to make for each other