Cisco 7941G Administration Manual page 247

Troubleshooting and Maintenance
Summary
Changing the telephone configuration
Phone resetting
Codec mismatch between the phone
and another device
Sound sample mismatch between the
phone and another device
Gaps in voice calls
Loopback condition
Cisco Unified IP Phone 7941G, 7941G-GE, 7942G, 7961G, 7961G-GE, and 7962G Administration Guide for Cisco Unified
Explanation
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
page 60 for details.
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.
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 Call Statistics Screen, on page 184
displaying these statistics.
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 Call Statistics Screen, on page 184
displaying these statistics.
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 Call Statistics Screen, on page 184
displaying these statistics.
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 or the power supply is
disconnected
In this case, the switch port on the phone can become disabled and
the following message appears in the switch console log:
HALF_DUX_COLLISION_EXCEED_THRESHOLD
To resolve this problem, re-enable the port from the switch.
Communications Manager 9.0 (SCCP and SIP)
General Troubleshooting Information
Unlock and Lock Options, on
for information about
for information about
for information about
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