I have a Plantronics C5220 USB-C headset and when I use it on Skype I can hear myself in the headset speakers, that's what they call "sidetone" (or voice feedback).
Apparently there is a native option on Windows OS to disable it, I wonder if there is any way to achieve that in macOS ?
I have already been through sound settings and midi/audio settings.
Best Answer
I got an answer from the Plantronics (Poly) support team, all their products have sidetone enabled.
On macOS, the driver (Plantronics Hub) they provide is not that good and doesn't allow to disable sidetone which is probably firmware enabled.
I've also tested the headset with the 3.5mm jack on my smartphone and the sidetone is not present that why I tend to think that the sidetone is handled by either Plantronics Hub or headset firmware.