They also do things like pump music/white noise in voids in walls.
There are guys that do nothing but try to come up with ways to hear conversations( and ways to beat it)
Sounds like a fun job actually.
Yes it does

The Soviets went as far as having their Communications section completely isolated from the out side, it is basically a spring mounted room inside a room.
Which is why both sides target the code CLERKS, like Gosenko and Ames.

The human link in the chain is always the weakest.