Why is there a loss of voice when using VAD, which codec should I use?

Question

Data transfer

Hello. When using VAD, I noticed that because of it, for some reason, there is either a loss, or I don’t know what, of voice data. The voice becomes broken.
Code taken from here: https://metanit.com/sharp/articles/VAD_filter.php
What could be the problem?
And yes, the voice is interrupted both locally and remotely.
I’ll also immediately ask here: what codec should I use to reduce traffic?

I will also add that I measured the speed of the method through Stopwatch, with and without VAD, the speed is identical.