popping noise (sometimes squealing) in iPhone SE 2020 earpiece

I've noticed the popping sound during certain phone calls since purchase. I've done all the resets (per Apple) and contacted my provider, as Apple recommended, but it wasn't a network issue. The sound occasionally turns into a squeal. Does anyone else have this problem? I've done some research and it appears the iPhone 8 had the same issue, which was fixed for most via a software patch (update).