I have an IP phone where I cannot hear the caller. The caller can hear me just fine but I am unable to hear the caller. I have used the speaker phone, handset and headset. IP Phone is plugged into the network switch. I have changed the NAT filtering, QoS priorities, DMZ settings. Trial and error. Same issue.
The IP Phone did work with the modem plugged into the switch and by pass the router. It also worked plugged directly into the modem. There has to be a setting on the router that I am missing.
Anyone else have any ideas?
Last speed test:
Cisco IP Phone 300
Yealink T21P E2
Firmware Version
V1.0.9.64_10.2.64
