Here is a funny video which has been around for quite some time.
Due to the poor audio quality of mobile phones, this (not so) poor lady cannot make the difference between her husband and a stranger.
With the switch to data, many manufacturers neglect the audio quality of their devices, or as they are coming from the IT world they just don’t have the know-how to make voice sound good.
The move from Orange and other operators to offer HD voice is an interesting one. Voice is still their milk cow and good audio can really help them to differentiate.