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Cisco Unified IP Phone 7965G and 7945G Administration Guide for Cisco Unified Communications Manager 6.0
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Chapter 9 Troubleshooting and Maintenance
General Troubleshooting Tips
Moving a network
connection from the
phone to a workstation
If you are powering your phone through the network
connection, you must be careful if you decide to
unplug the phone’s network connection and plug the
cable into a desktop computer.
Caution The computer’s network card cannot
receive power through the network
connection; if power comes through the
connection, the network card can be
destroyed. To protect a network card, wait
10 seconds or longer after unplugging the
cable from the phone before plugging it
into a computer. This delay gives the
switch enough time to recognize that there
is no longer a phone on the line and to stop
providing power to the cable.
Changing the telephone
configuration
By default, the network configuration options are
locked to prevent users from making changes that
could impact their network connectivity. You must
unlock the network configuration options before you
can configure them. See the
“Unlocking and Locking
Options” section on page 4-3 for details.
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.
Table 9-2 Cisco Unified IP Phone Troubleshooting (continued)
Summary Explanation