I have perfect pitch and can hear some of the mid-range notes (just a few) slightly off key and even distorted at times.
Do they have the option to turn off some of the processing?
IIRC various noise reduction etc processing works in freq bands, which can result in artifacts like you described.
My wife didn't want me to get the behind the ear models which certainly would have been better because she didn't want me to look like an 'old man'. I did go to Costco but I wanted the smallest and best available which they didn't have.
That shouldn't be an issue unless you have a shaved head and ears that stick out.
My Rextons and many others I've seen are small enough to tuck behind the ears and are available in a few colors to match your hair.
The only visible part is the thin clear tubes that run into the ear canal, and virtually no one notices them; people are always surprised to find out I have HA's.