Thank WIY for bringing this up. I wondered about that for years.
Squeak- well said.
It’s also a serious problem because according to many Poskim one is not yotzei saying the Shem Hashem when saying ‘Ado- rather one must say Adoi-
A few years back when I found out about this, I informed my mother and since then she’s been careful during davening to pronounce the Shem Hashem correctly.
Sadly many people that try to be machmir in other things don’t know about this.
An even worse problem is when people pronounce Hashems Name as Adi-noy, which according to virtually all Poskim is not valid.
Very common unfortunately. Just listen to Chazaras Hashatz. It’s a mitzvah to publicize this.