I’m so pleased I was able to find this group. I am in UK and have also purchased the iPhone 12 Pro and have been encountering the static sounds in my Specsavers Advance hearing aids (I think they are Signia NX’s). Have been onto Apple Support via chat and they say they haven’t any reported issues. Guess it depends on what resources ythey are able to access. I am going to send them a link to this chat, so that they stop send me off on wild goose chases.
Looking forward to a resolution to this issue.