The only "echo" is this.
"Microphone Monitoring
Hear your voice in the headset, so you won't have to shout to hear what you're saying."
And trust me, without this feature, you wouldn't be able to hear yourself that well, the ear muffs cup over your ears perfectly, reducing the sound heard around you. You can hear what you're saying but it's not all that bad. The only way to turn this off is by muting the mic itself. If it bothers you too much, you can just move the mic further from your mouth.