Hi,
We recently received a shipment of Cisco 8841,7821 Phones and Plantronics HW520 headsets but the headsets don't work however if I try the same headset on our old phones Cisco 7942 it works I tried another third party headsets Jabra they work on 8841,7821 Phones. Is there any setting that I need to enable on the Phones, Please advice.