Cisco 852 Headset

[sfrattini]

I cannot hear myself speaking in the new Cisco 852 headset. Everyone can hear me and I can hear them, but my voice isn't routing through the headset mic into the headset earphones.  

[Ashish Patel]

Cisco don't have a headset 852 model...
Are you using Cisco IP Phone - have you confirmed you have the right cable and connectors etc and accessory is not disabled etc.
Can you just test making a call from phone/pc to your own mobile and test whether you can hear sound etc...
Need more details.