Cisco 7962G Administration Guide

9-11
Cisco Unified IP Phone Administration Guide for Cisco Unified Communications Manager 7.1
OL-18913-01
Chapter 9 Troubleshooting and Maintenance
General Troubleshooting Tips
Phone resetting. The phone resets when it loses contact with the Cisco Unified Communications
Manager software. This lost connection can be due to any network connectivity
disruption, including cable breaks, switch outages, and switch reboots.
LCD display issues. If the display appears to have rolling lines or a wavy pattern, it might be
interacting with certain types of older fluorescent lights in the building.
Moving the phone away from the lights, or replacing the lights, should resolve
the problem.
Dual-Tone Multi-Frequency (DTMF)
delay.
When you are on a call that requires keypad input, if you press the keys too
quickly, some of them might not be recognized.
Codec mismatch between the phone and
another device.
The RxType and the TxType statistics show the codec that is being used for a
conversation between this Cisco Unified IP phone and the other device. The
values of these statistics should match. If they do not, verify that the other
device can handle the codec conversation, or that a transcoder is in place to
handle the service.
See the “Call Statistics Screen” section on page 7-13 for information about
displaying these statistics.
Sound sample mismatch between the
phone and another device.
The RxSize and the TxSize statistics show the size of the voice packets that are
being used in a conversation between this Cisco Unified IP phone and the other
device. The values of these statistics should match.
See the “Call Statistics Screen” section on page 7-13 for information about
displaying these statistics.
Gaps in voice calls. 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.
See the “Call Statistics Screen” section on page 7-13 for information about
displaying these statistics.
Loopback condition. A loopback condition can occur when the following conditions are met:
• The SW Port Configuration option in the Network Configuration menu on
the phone is set to 10 Half
(10-BaseT / half duplex)
• The phone receives power from an external power supply
• The phone is powered down (the power supply is disconnected)
In this case, the switch port on the phone can become disabled and the
following message will appear in the switch console log:
HALF_DUX_COLLISION_EXCEED_THRESHOLD
To resolve this problem, re-enable the port from the switch.
One-way audio. When at least one person in a call does not receive audio, IP connectivity
between phones is not established. Check the configurations in routers and
switches to ensure that IP connectivity is properly configured.
Table 9-2 Cisco Unified IP Phone Troubleshooting (continued)
Summary Explanation

Cisco 7962G Specifications

General

Mounting	Desk/Wall
Handset type	Wired handset
Product type	IP Phone
Case material	ABS
Product color	Black, Grey
Wall mountable	Yes
Bluetooth	No
Security algorithms	128-bit AES, 802.1x RADIUS
Networking standards	IEEE 802.1Q, IEEE 802.1p, IEEE 802.1x, IEEE 802.3af
Ethernet LAN data rates	10, 100 Mbit/s
Ethernet LAN interface type	Fast Ethernet
Ethernet LAN (RJ-45) ports	2
Voice codecs	G.711, G.711a, G.722, G.729A, G.729ab, iLBC
Volume control	Digital
Display diagonal	5 \
Display resolution	320 x 222 pixels
Display number of colors	Monochrome
Caller ID	-
Lines quantity	- lines
Phonebook capacity	- entries
Storage temperature (T-T)	-10 - 60 °C
Operating temperature (T-T)	0 - 40 °C
Operating relative humidity (H-H)	10 - 95 %
Number of handles included	1 pc(s)

Weight and Dimensions

Depth	203.2 mm
Width	266.7 mm
Height	152.4 mm
Weight	1600 g