I have a Logitech desktop mic (USB) with which I have a quite strange problem with it. It works fine on Windows, so I know it isn't the mic itself.
I use the mic mostly for Skype conversations. I know Skype is a POS software (on Linux as well as Android, and Windows isn't much better either), but try convincing everyone to switch. Anyway, I make the test call fine, and I make regular calls fine, but here's the thing. When someone calls me, they can't hear me. When I call them, they hear me. But even when I call them and we talk, they can't hear me while they're talking. In other words, I can't interrupt them while they're talking. So unless Skype decided to implement a RudeFree (tm) technology that I'm unaware of, I think there's something wrong with my mic - or possibly Skype.
The second question is: might PulseAudio solve this issue? I stay away from PulseAudio because in the past it has given me nothing but trouble (and I can see that I am not alone in that). However, I also see people saying that it has improved a lot. The reason I am not installing it and trying it myself right now is because I also remember that I had a hard time removing it as well.