I can so relate (me and my dear late Mum) wore various kinds of hearing aids, for many years-and the only one I can suggest-think is the same one Angie said it, too- the most basic paper(surgical) mask- think they have the thinnest narrowest elastic there behind the ears which can fit under the BTE's the best way.
I now have a cochlear implant which surely is the best thing in the hard of hearing's world but am suddenly dealing rather with another kind of problem- I still aid myself some with reading people's speach from their lips- so now that everybody has to cover theirselves it is very hard again....In an (of course, not so-but) ideal COVID world masks would be all of transparent plexyglass. I only hope this too shall pass:-) as soon as possible...
