I use latest version 3.27 of PhonerLite x64. 

Everything works ok on MicroSIP so it's not a provider problem and it is not a weak machine problem (16Gb, Ryzen 5 Pro).

On previous versions of PhonerLite the problems were the same.
G711.u, G711.a, G722WB, G729, SRTP, SAVP are checked.

After few minutes or sometimes even seconds after the call start voice starts breaking more and more until the app closes without any errors displayed.