All good day
There are Lumia 950 WindowsPhone 10, installed Zoiper 1.0.44 (if memory does not change)
problem: I do not hear what I say.
If you use a home WiFi network connection is working properly and efficiently.
If you are using a 4 g/3 g mobile network-I hear, and I don't.
in the settings, tried different, can't find that would help.
Audio a-law codec installed, just tried u-law.
operator Megafon Rus.