Cisco 7800 Series Administration Guide

Audio Problems
The following sections describe how to resolve audio problems.
No Speech Path
Problem
One or more people on a call do not hear any audio.
Solution
When at least one person in a call does not receive audio, IP connectivity between phones is not established.
Check the configuration of routers and switches to ensure that IP connectivity is properly configured.
Choppy Speech
Problem
A user complains of choppy speech on a call.
Cause
There may be a mismatch in the jitter configuration.
Solution
Check the AvgJtr and the MaxJtr statistics. A large variance between these statistics might indicate a problem
with jitter on the network or periodic high rates of network activity.
General Telephone Call Problems
The following sections help troubleshoot general telephone call problems.
Phone Call Cannot Be Established
Problem
A user complains about not being able to make a call.
Cause
The phone does not have a DHCP IP address. The phones display the message Configuring IP or
Registering.
Cisco IP Phone 7800 Series Multiplatform Phones Administration Guide
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Cisco IP Phone Troubleshooting
Audio Problems

Cisco 7800 Series Specifications

General

Wireless	No
Video Support	No
PoE	Yes, 802.3af/at
Audio Codec Support	G.711, G.722, G.729, iLBC
Network Protocols	SIP, SDP, IPv4, IPv6, UDP, TCP, DNS, TFTP, HTTP, HTTPS, DHCP
Security Features	802.1X, TLS, SRTP
Power Options	PoE
Headset Port	3.5mm
Buttons	Line keys, navigation cluster, softkeys, mute, speakerphone, headset, volume control
Bluetooth	No
Ethernet Switch	Yes, 2-port 10/100/1000
USB Port	Yes, for headset (7875)