When a teammate hears their own voice, start with the simplest possibility: sound from your headset or TV is leaking back into the microphone. Lower the game and chat volume for a moment, then ask whether the echo changes.
Check the microphone path
Move the microphone slightly to the side of your mouth, about a finger-width away. Make sure the microphone opening is not pointed directly at the earcup. If your setup has a mute switch, toggle it once to confirm the input is being recognized.
Check the output device
Confirm that chat audio is going to the headset rather than the television or monitor. On a computer, open the sound settings and make sure the headset is selected for both input and output.
Test one change at a time
Echo is much easier to solve when you change one setting, test, and keep the result. If the issue follows one controller or one app, the headset may be fine and the problem may be in that device's chat routing.
Save this guide, share it with your squad, and explore the HCG1 setup when you are ready for a simple, wired connection.